Retire fixed input and transport caveats (V-688)

Also removes resolved V-675, V-676, and V-679 entries. The owner explicitly requested direct commits on master; --no-verify bypasses the branch-only workflow hook.

docs/caveats/CLAUDE.md

@@ -22,10 +22,12 @@ caveat is the pointer between them plus the trigger.
 
 Every entry below came from the 2026-08-10 deep audit
 (`docs/evals/2026-08-10-repo-audit.md`), except the last, which came from wiring
-the gate the audit asked for. Five of the twenty findings are fixed and have no
+the gate the audit asked for. Nine of the twenty findings are fixed and have no
 entry. The unauthenticated mavgpud proxy was V-673. The 20 reachable advisories
 in the toolchain and `x/text` were V-682. The missing analyzers were V-694, and
-what they now report is the baseline entry under V-701. The two unguarded
+what they now report is the baseline entry under V-701. The invalid STT and
+weather responses were V-675/V-676, the stuck TCP close was V-679, and the
+unbounded PTT path was V-688. The two unguarded
 invariants were V-692 and V-693, and their guards are described in
 `docs/routing.md`.
 
@@ -33,13 +35,9 @@ invariants were V-692 and V-693, and their guards are described in
 | --- | --- |
 | [Anyone past the proxy can enroll a passkey](security.md#enrollment) | high |
 | [Passkey credentials are rewritten in place](security.md#credentials) | medium |
-| [An empty STT transcript reads as a successful one](external-inputs.md#stt) | medium |
-| [Open-Meteo's empty body becomes 0°C](external-inputs.md#weather) | medium |
 | [Dialogue persistence errors are swallowed](storage.md#dialogue) | medium |
 | [The reminder transition is a lost update](storage.md#reminders) | medium |
 | [A recall miss scans two whole tables](storage.md#recall) | medium |
-| [Closing a TCP listener can strand Accept](transport.md#accept) | medium |
-| [PTT reads an unbounded body](transport.md#ptt) | medium |
 | [mavweb errors cannot be traced](transport.md#errors) | medium |
 | [Fact enrichment is a 20-call serial waterfall](workers.md#enrichment) | medium |
 | [A suppressed nudge is phrased anyway](workers.md#nudges) | medium |

docs/caveats/external-inputs.md

@@ -1,20 +0,0 @@
-# External inputs
-
-What arrives from a service Maven does not run, and what happens when it
-arrives malformed. The shared shape: a JSON decode into value fields cannot
-tell "absent" from "zero", so a degraded response becomes a confident answer.
-
-## An empty STT transcript reads as a successful one [#675] {#stt}
-
-Costs: one dropped voice turn per malformed 200 from workpc. The mavsttd floor
-is never asked, because `stt.Pair` falls back on a non-nil error alone.
-Revisit when: CW2 returns a 200 with no text. Sooner if a proxy is put between
-homesrv and port 8081.
-Workaround: none. It is silent by design and the fallback is never spoken.
-
-## Open-Meteo's empty body becomes 0°C [#676] {#weather}
-
-Costs: he is told the weather is clear and 0°C when the service answered
-nothing. Distinct from V-589, which covered the HTTP status and not the body.
-Revisit when: a weather answer is reported as wrong, or the geocoder changes.
-Workaround: none.

docs/caveats/transport.md

@@ -3,28 +3,6 @@
 The HTTP and socket seams. What a client can do to them, and what a shutdown
 can do to us.
 
-## Closing a TCP listener can strand Accept [#679] {#accept}
-
-Costs: during close, both `errc` and `done` are ready in `acceptLoop`'s select.
-Go picks uniformly. So roughly one close in two leaves a waiting `Accept`
-blocked forever on a TCP seam. Unix sockets are unaffected.
-Revisit when: a daemon is seen hanging on shutdown, or before any new TCP
-listener is added.
-Workaround: the process usually exits anyway, which hides it.
-
-## PTT reads an unbounded body [#688] {#ptt}
-
-Costs: `handlePTT` does an unlimited `io.ReadAll`, and mavweb sets no header or
-idle timeouts. A client can force unbounded allocation or hold a connection
-open. mavgpud's half of this was fixed in V-673.
-Revisit when: mavweb is reachable from anything but the tunnel.
-Workaround: mavweb is not LAN-exposed today.
-
-`/ws` rides along with this entry. It never calls `SetReadLimit`, so the
-dependency default of 32,768 bytes applies, about a second of audio. Nothing
-reaches it: the browser posts PCM to `/api/ptt`, and only `handlers_test.go`
-opens `/ws`. It gets a caller and a real limit, or it gets deleted.
-
 ## mavweb errors cannot be traced [#689] {#errors}
 
 Costs: some handlers return the raw internal error, which discloses internals.