v0.8.0

v0.8.0 — proactive recall, selectable embedding model, full MCP control

The release that makes the brain proactive and gives the agent (and user)
full control over it from inside Claude Code / Codex.

ADDED

• Proactive recall (mid-work). New PreToolUse / PostToolUse Bash hooks
  surface a relevant memory while the agent works, not just on prompt:
  • after a failed Bash command, surface a matching failure_pattern /
    command fix;
  • before a risky Bash command, warn from a matching failure_pattern;
  • on a repeated failing command (loop), lower the score floor and bypass
    the throttle so help arrives sooner.
    Retrieval is lexical-FTS-only (no embedding-model load), gated by a high
    score floor (0.45; loop 0.35), capped at one capsule, with per-session
    dedupe + a refractory throttle. Token cost stays ~0 (silent when nothing
    qualifies). Wired into both Claude Code (.claude/settings.json) and Codex
    (.codex/hooks.json) with a matcher: "Bash"; opt out with
    kimetsu plugin install --no-proactive (or proactive:false over MCP).
    Per-session state lives in <repo>/.kimetsu/proactive/<session_id>.json
    and is garbage-collected after 7 days.
• Selectable embedding model. New [embedder] table in project.toml
  (precedence: KIMETSU_BRAIN_EMBEDDER env > config > default). Inspect and
  change it with kimetsu brain model list / kimetsu brain model set <id>
  (the latter writes the config and re-embeds the corpus with the new model).
  Curated built-ins: bge-small-en-v1.5 (384d, default), bge-m3 (1024d),
  jina-v2-base-code (768d).
• Full MCP control surface. New tools so an agent can manage the brain
  without leaving Claude Code / Codex: kimetsu_brain_model_list /
  kimetsu_brain_model_set (re-embeds in-process with the new model),
  kimetsu_brain_reindex, kimetsu_brain_memory_search (FTS over memory
  text), kimetsu_brain_conflict_resolve, kimetsu_brain_prune, and
  kimetsu_brain_config_show. kimetsu_brain_memory_list and
  ..._memory_proposals gained limit/offset pagination.

CHANGED

• reindex can now run against an explicit embedder
  (reindex_all_with_embedder), so a model switch re-embeds with the chosen
  model regardless of the process's cached default embedder.

FIXED

• Test isolation. Tests created project roots under the system temp dir;
  on a machine whose $HOME is itself a git repo, ProjectPaths::discover
  climbed to $HOME and made parallel tests share one brain.db +
  project.lock. Each test root now gets its own git boundary, so plain
  cargo test is hermetic.