Correct flagged-skill reporting split in TELEMETRY (#1004)

* docs(telemetry): correct flagged-skill reporting split

Eight listed/loadable, git-worktrees explicit-only, two bake-only; seven reported, four custom. Part of CL-7931.

* docs(telemetry): sync skill taxonomy comment with reporting split

The allowlist comment still described four bake-only background skills while TELEMETRY documents native-integration and ponytail as listed and loadable.

Author: TheGreatAxios

docs/TELEMETRY.md

@@ -83,12 +83,12 @@ name from the closed `corbits-skills` allowlist (`ast-grep`, `create-issue`,
 `pull-request-review`, `refactor`, `review`, `scribe`, `style`,
 `typescript`), or `custom` for anything else. `user-invocable: false` opts a
 skill out of slash synthesis, not out of name reporting: eleven bundled
-skills carry the flag, and seven of them (`git-rebase`, `git-worktrees`,
-`linear-issue-workflow`, `opsh`, `philosophy`, `style`, `typescript`)
-remain real `use_skill` recipes, so they stay on the allowlist — the names
-are ours either way. Excluded are the four bake-only background skills
-(`idiot-proof`, `native-integration`, `native-runtime`, `ponytail`), which
-are baked into agent prompts rather than invoked as skills. Unknown,
+skills carry the flag — eight stay listed and loadable (`git-rebase`,
+`linear-issue-workflow`, `opsh`, `philosophy`, `style`, `typescript`,
+`native-integration`, `ponytail`), `git-worktrees` resolves by explicit name
+only, and two stay hidden bake-only (`idiot-proof`, `native-runtime`). Of
+the eleven, seven are reported by name and four stay `custom` (pinned;
+conservative under-reporting, never a leak). Unknown,
 project-local, and plugin-authored skill names are never transmitted —
 `skill_name` is the only identifying-adjacent property the event can carry.
 `plugin_loaded` goes further: there is no first-party list of plugins to

src/telemetry/classify.ts

@@ -77,13 +77,14 @@ const BUILT_IN_AGENT_NAMES: ReadonlySet<string> = new Set([
 // plugin id and kind — no skill list — so the closed set is spelled out here
 // and pinned by tests/unit/telemetry-product-events.test.ts.
 // `user-invocable: false` is a slash-surface flag, not a telemetry flag:
-// eleven bundled skills carry it, and seven of them (git-rebase,
-// git-worktrees, linear-issue-workflow, opsh, philosophy, style, typescript)
-// opt out of slash synthesis yet remain real `use_skill` recipes, so they
-// stay reportable by name. Excluded are the four bake-only background skills
-// (idiot-proof, native-integration, native-runtime, ponytail), which are
-// baked into agent prompts rather than invoked as skills. Project- or
-// plugin-authored skills are never reported by name.
+// eleven bundled skills carry it — eight stay listed and loadable
+// (git-rebase, linear-issue-workflow, opsh, philosophy, style, typescript,
+// native-integration, ponytail), `git-worktrees` resolves by explicit name
+// only, and two stay hidden bake-only (idiot-proof, native-runtime), which
+// are baked into agent prompts rather than invoked as skills. Of the eleven,
+// seven are reported by name and four stay `custom` (pinned; conservative
+// under-reporting, never a leak). Project- or plugin-authored skills are
+// never reported by name.
 const FIRST_PARTY_SKILL_NAMES: ReadonlySet<string> = new Set([
   "ast-grep",
   "create-issue",