Deliver the compaction briefing through the hook that can inject it

[zzet]

Investigating #70 turned up that the reporter was right about the mechanism, and that a gortex-side bug sitting underneath it was worse than the issue itself.

The PreCompact briefing never reached the model

runPreCompact emitted its orientation snapshot as hookSpecificOutput.additionalContext. PreCompact has no context-injection contract in Claude Code. Per the hooks reference, additionalContext is honoured for SessionStart, Setup, SubagentStart, the tool events, Stop and SubagentStop; PreCompact's only documented output is a top-level decision: "block" (or exit 2), both of which block compaction. Its plain stdout is not context either — only UserPromptSubmit, UserPromptExpansion and SessionStart get that.

So the entire briefing — graph stats, symbol history, hotspots, feedback, and the "do not re-read indexed files" instruction — was discarded. As far as I can tell it never worked.

It now ships from SessionStart(source="compact"), which does honour additionalContext and fires once the new window is built. The Source field was already parsed and already carried "compact"; it was simply never read. Gortex registers SessionStart with no matcher, so no installer change is needed.

The block now says why it matters

This is the substance of #70. Compaction rebuilds the window from the summary, the most recent exchanges, and up to five recently-read files, which Claude Code re-reads from disk and re-injects as system-reminder blocks. That path invokes the Read tool directly, so no PreToolUse hook sees it and none of gortex's redirects to graph tools apply — the agent wakes up holding raw whole-file content it never asked for, and will happily read those files again.

The briefing degrades to advisory-only when the bridge is unreachable, rather than to silence as before: the advisory costs no daemon call and is the half that actually changes what the agent does next.

PreCompact stays registered so hook-effectiveness telemetry still records compactions, and now emits nothing.

Second fix: the doubled version prefix

The daemon status line rendered vv0.63.2 on every session start — the same shape reported in #70 as vv0.41.0+29a0849. StatusResponse.Version arrives already v-prefixed and renderDaemonReadiness added its own literal v at all three of its daemon-state branches.

renderLeanReadiness directly above it already trimmed the prefix, which made this look half-fixed. It is not — no shipped instruction profile selects the lean tier, so that renderer never runs and every real session took the broken path. Both now route through one helper, tolerant of an unprefixed value because canonicalVersion's fallback branch returns one.

Docs

• docs/agents.md listed 4 installed hooks; the installer writes 8. Also documents why the post-compaction block hangs off SessionStart.
• docs/features.md claimed PreCompact injects the snapshot.

docs/agents.md:318's "PreCompact / PostCompact — Not installed" row is not wrong and is untouched: it sits under the Codex "Intentional Codex lifecycle gaps" table.

Verification

Unit tests plus an end-to-end run of the built binary against a live daemon:

payload	result
SessionStart source=compact	block + advisory + rule preamble, no vv
SessionStart source=startup	no block; renders (v0.63.2-39-g78a79eaf+78a79eaf, …), previously (vv0.63.2-…
PreCompact	0 bytes stdout, 0 bytes stderr

go test -race ./internal/hooks/ passes and golangci-lint reports 0 issues. The first commit was checked out standalone to confirm it compiles, since the two fixes were split out of one file.

Not addressed here

Three defects found during the investigation, deliberately left out of this PR:

• HookTierLean is unreachable — no shipped profile selects it, so renderLeanReadiness is dead code. Wiring bug or reserved tier is a product call.
• trackedRepoForPath (session_paths.go:210) compares paths byte-exactly, which fails on any case-insensitive filesystem — macOS as much as Windows — while a case-folding helper exists and is used elsewhere. Live enforcement hole.
• The baked hook command (claudecode/hooks.go:131) is unquoted, so an install path containing a space yields a command the shell splits and no hook fires. Latent, every OS.

Refs #70.