docs(backlog): record idea-promotion (f107ff5); mark plan-comparison blocked

f107ff5 (idea-board -> profile promotion) moves to RETRO. Plan-comparison view marked
BLOCKED: no plan-candidate event exists server-side (only workflow.proposed), so there
is no wire shape to render or unit-verify until a multi-candidate planner lands.

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

RETRO.md

@@ -33,6 +33,7 @@ Nine tracks, each compiled + unit-tested green before commit.
 | `641051b` | Plan-derived diff manifest: `PlanStage.writes` + `PlanDerivedManifest.deriveAllowedWrites`/`combine`, unioned into `StageConfig.writeManifest` at compile, enforced by the existing containment matcher | B §2 |
 | `ab7e4be` | Egress allowlist **activation**: `resolveSessionEgressHosts` threads the session's `EgressAllowlistProjection` state into `ToolCallAssessmentInput` at `runPlane2Assessment`, so `NetworkHostRule` now consults the live per-session union (was fed `emptySet()`) | D (activation) |
 | `4b0024f` | Batch source-list fetch-approval: `POST /sessions/{id}/approve-sources` → `SourceListHosts.extract` (java.net.URI, lower-cased, ports stripped, dossier-line tolerant) → one `EgressHostsGrantedEvent`; live allowlist then auto-clears those web_fetches (no per-URL T2) | D |
+| `f107ff5` | Idea-board → project-profile promotion: `IdeaPromotedEvent` (board tombstone, like discard) + `ProjectProfileWriter` (escape-aware TOML serialize/write) + `ProjectProfile.withConvention` (deduped) + server `PromoteIdea` handler (loads profile, appends idea text, writes `.correx/project.toml`); also made `SimpleToml`'s reader unescape `\\`/`\"` symmetrically with the writers (fixes pre-existing read/write asymmetry) | E |
 
 ### Follow-ups created this pass (refiled into BACKLOG)
 - **C-A1 activation** — `planner.md` must emit a `brief_echo` block and `role_pipeline.toml` must set `briefEcho="true"` / `briefEchoSource` for the gate to fire live (model-dependent → live-QA).