chore(subagents): log TASK-100 execution handoff

docs/subagents/INDEX.md

@@ -62,4 +62,5 @@ Read first. Keep concise.
 | `opencode-task84-keybindings-gating-20260222T011624Z-llor`    | `opencode-task84-keybindings-gating`    | `Execute TASK-84 gate feature-dependent keybindings behind config flags end-to-end without commit`                   | `done`        | `docs/subagents/agents/opencode-task84-keybindings-gating-20260222T011624Z-llor.md`    | `2026-02-22T01:35:30Z` |
 | `codex-task98-source-tests-20260222T021156Z-a1b2`             | `codex-task98-source-tests`             | `Execute TASK-98 shift core tests to source level and trim dist coupling end-to-end without commit`                  | `done`        | `docs/subagents/agents/codex-task98-source-tests-20260222T021156Z-a1b2.md`             | `2026-02-22T02:36:00Z` |
 | `codex-task101-docs-archive-20260222T024156Z-hneu`            | `codex-task101-docs-archive`            | `Execute TASK-101 consolidate architecture docs and archive task-noise evidence`                                     | `done`        | `docs/subagents/agents/codex-task101-docs-archive-20260222T024156Z-hneu.md`            | `2026-02-22T03:01:38Z` |
-| `codex-fix-ci-20260222T025848Z-0xdl`                          | `codex-fix-ci`                          | `Inspect failing GitHub Actions PR checks and implement approved fix`                                                | `in_progress` | `docs/subagents/agents/codex-fix-ci-20260222T025848Z-0xdl.md`                          | `2026-02-22T02:58:55Z` |
+| `codex-fix-ci-20260222T025848Z-0xdl`                          | `codex-fix-ci`                          | `Inspect failing GitHub Actions PR checks and implement approved fix`                                                | `done`        | `docs/subagents/agents/codex-fix-ci-20260222T025848Z-0xdl.md`                          | `2026-02-22T03:25:40Z` |
+| `opencode-task100-dead-code-prune-20260222T033155Z-qenz`      | `opencode-task100-dead-code-prune`      | `Execute TASK-100 dead-code prune and cleanup via writing-plans + executing-plans (no commit)`                       | `done`        | `docs/subagents/agents/opencode-task100-dead-code-prune-20260222T033155Z-qenz.md`      | `2026-02-22T04:00:41Z` |

docs/subagents/agents/opencode-task100-dead-code-prune-20260222T033155Z-qenz.md

@@ -0,0 +1,57 @@
+# Agent Session: opencode-task100-dead-code-prune-20260222T033155Z-qenz
+
+- alias: `opencode-task100-dead-code-prune`
+- mission: `Execute TASK-100 dead-code prune and cleanup via writing-plans + executing-plans (no commit).`
+- status: `done`
+- started_utc: `2026-02-22T03:32:21Z`
+- last_update_utc: `2026-02-22T04:00:41Z`
+
+## Intent
+
+- Load TASK-100 from Backlog MCP and capture a concrete execution plan.
+- Run dead-code candidate discovery with import/export checks and safe pruning.
+- Preserve behavior with regression-safe removals and gate verification.
+
+## Planned Files
+
+- `src/**/*.ts`
+- `scripts/**/*.ts`
+- `package.json`
+- `docs/**/*.md`
+- `docs/plans/*.md`
+
+## Files Touched
+
+- `docs/subagents/agents/opencode-task100-dead-code-prune-20260222T033155Z-qenz.md`
+- `docs/subagents/INDEX.md`
+- `docs/subagents/collaboration.md`
+- `docs/plans/2026-02-22-task-100-dead-code-prune-cleanup.md`
+- `docs/reports/2026-02-22-task-100-dead-code-report.md`
+- `src/anki-connect.ts`
+- `src/anki-integration.ts`
+- `src/anki-integration/card-creation.ts`
+- `src/anki-integration/ui-feedback.ts`
+- `src/core/services/anki-jimaku-ipc.ts`
+- `src/core/services/immersion-tracker-service.ts`
+- `src/core/services/ipc-command.ts`
+- `src/renderer/positioning/position-state.ts`
+- `src/tokenizers/index.ts`
+- `src/token-mergers/index.ts`
+- `src/core/utils/index.ts`
+
+## Assumptions
+
+- TASK-100 scope is code/test/docs cleanup only; no feature behavior changes.
+- Existing guardrails (`check:file-budgets`, runtime-cycle check, tests) are available.
+- Parallel subagents can split dead-code scan and docs/report updates safely.
+
+## Phase Log
+
+- `2026-02-22T03:32:21Z` Session started; loaded backlog overview/TASK-100 and subagent coordination files.
+- `2026-02-22T03:39:55Z` Wrote execution plan in `docs/plans/2026-02-22-task-100-dead-code-prune-cleanup.md` and started implementation.
+- `2026-02-22T03:49:20Z` Parallel subagents completed dead-code candidate analysis and safe-removal shortlist.
+- `2026-02-22T04:00:41Z` Completed dead-code removals + report, verified required gates, and finalized TASK-100 as Done in Backlog MCP.
+
+## Next Step
+
+- Finalize TASK-100 in Backlog MCP with report path and verification evidence.

docs/subagents/collaboration.md

@@ -87,3 +87,5 @@ Shared notes. Append-only.
 - [2026-02-22T02:36:00Z] [codex-task98-source-tests-20260222T021156Z-a1b2|codex-task98-source-tests] completed TASK-98 closure: validated `test:fast` + `build` + `test:smoke:dist` all pass on current HEAD, captured timing repro (`2.18s` source lane, `0.21s` dist smoke), confirmed script/workflow/docs split unchanged, and finalized Backlog task to Done.
 - [2026-02-22T02:41:56Z] [codex-task101-docs-archive-20260222T024156Z-hneu|codex-task101-docs-archive] starting TASK-101 via Backlog MCP + writing-plans/executing-plans; scope architecture docs consolidation, stale-note cleanup, archive evidence retention, and docs link/build verification.
 - [2026-02-22T03:01:38Z] [codex-task101-docs-archive-20260222T024156Z-hneu|codex-task101-docs-archive] completed TASK-101: canonicalized runtime architecture wording in `docs/architecture.md`, trimmed duplicated architecture bullets in `docs/development.md`, converted `docs/structure-roadmap.md` to archival notice, `bun run docs:build` passed, and backlog TASK-101 finalized Done with AC/DoD evidence.
+- [2026-02-22T03:32:21Z] [opencode-task100-dead-code-prune-20260222T033155Z-qenz|opencode-task100-dead-code-prune] starting TASK-100 via Backlog MCP + writing-plans/executing-plans; expected scope dead-code candidate report, safe removals, regression tests/gates, and backlog evidence updates.
+- [2026-02-22T04:00:41Z] [opencode-task100-dead-code-prune-20260222T033155Z-qenz|opencode-task100-dead-code-prune] completed TASK-100 execution pass: removed confirmed dead imports/helpers/exports across Anki/core/renderer/provider modules, added dead-code report at `docs/reports/2026-02-22-task-100-dead-code-report.md`, verified build + core/config src tests + file-budget checks, and prepared Backlog finalization updates.