feat(ecosystem): compliant Praxis/Hexis integration + vendored build

Bring the Nexus/Praxis/Hexis integration in line with
MAVEN_ECOSYSTEM_ARCHITECTURE.md:

- Praxis over HTTP: drop the in-process praxis.db open (praxisstore/
  praxistools) and call praxisd's /api/v1/tools/* API via a new praxisClient.
  Honors the "no component reads another's DB" invariant (AC#12).
  PraxisConfig.DBPath -> URL.
- Hexis confirmation gate: mutating capabilities (ReadOnly=false) now park a
  bound pendingHexis confirmation and require a spoken "да" before executing;
  read-only run immediately (AC#7, no auto attention->action).
- Capability safety: >1 verb match is ambiguous -> ask instead of firing the
  first; ambiguous Nexus resolution asks for clarification (AC#2).
- Correlation IDs on Hexis execute, recorded in the cross-service trace.
- Bug: importance arrives as JSON float64 over HTTP, not int.
- Tests: confirm-gate, decline, read-only, and ambiguity paths.

Build: vendor/ bakes in the hexis client (replace-directed at a sibling repo
outside the Docker context); Dockerfile builds from vendor and no longer
`go mod download`s the unreachable replace paths.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

vendor/modernc.org/libc/pthread/capi_darwin_amd64.go

@@ -0,0 +1,7 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_darwin_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{
+	"__darwin_check_fd_set_overflow": {},
+}

vendor/modernc.org/libc/pthread/capi_darwin_arm64.go

@@ -0,0 +1,7 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_darwin_arm64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{
+	"__darwin_check_fd_set_overflow": {},
+}

vendor/modernc.org/libc/pthread/capi_freebsd_386.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_freebsd_386.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_freebsd_amd64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_freebsd_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_freebsd_arm.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_freebsd_arm.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_freebsd_arm64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_freebsd_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_illumos_amd64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_illumos_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_386.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -o pthread/pthread_linux_386.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_amd64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_linux_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_arm.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -o pthread/pthread_linux_arm.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_arm64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -o pthread/pthread_linux_arm64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_loong64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_linux_loong64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_mips64le.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_linux_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_ppc64le.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_linux_ppc64le.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_riscv64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -o pthread/pthread_linux_riscv64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_linux_s390x.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -o pthread/pthread_linux_s390x.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_netbsd_amd64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_netbsd_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_netbsd_arm.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_netbsd_arm.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_openbsd_386.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_openbsd_386.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_openbsd_amd64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_openbsd_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_openbsd_arm64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_openbsd_arm64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_windows_386.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread/gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -ignore-unsupported-alignment -o pthread/pthread_windows_386.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_windows_amd64.go

@@ -0,0 +1,5 @@
+// Code generated by 'ccgo pthread\gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -o pthread\pthread_windows_amd64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{}

vendor/modernc.org/libc/pthread/capi_windows_arm64.go

@@ -0,0 +1,9 @@
+// Code generated by 'ccgo pthread\gen.c -crt-import-path  -export-defines  -export-enums  -export-externs X -export-fields F -export-structs  -export-typedefs  -header -hide _OSSwapInt16,_OSSwapInt32,_OSSwapInt64 -o pthread\pthread_windows_arm64.go -pkgname pthread', DO NOT EDIT.
+
+package pthread
+
+var CAPI = map[string]struct{}{
+	"daylight": {},
+	"timezone": {},
+	"tzname":   {},
+}