compression: fix auto-compress no-op on few-huge-messages + honest status ...

Root cause: the compression gate (should_compress) measures tokens, but the
partition measures message/turn count, and CompressionStarted was emitted
before the attempt. For navi_code's "few very large messages" shape (one big
file read = 1 user + assistant + 1 huge tool result, 66k tokens in 3 messages)
the gate fired, the UI showed "compression", but partition returned
to_summarize=[] -> compress_context None -> nothing shrank. The agent kept
going until the window overflowed. It wasn't running "during" compression —
there was no compression, just a no-op the user mistook for one.

A. Per-message head/tail truncation in context_builder.build(): oversized
   tool/assistant messages (over context_message_token_budget, 0=num_ctx//6)
   are capped head+marker+tail in the LLM view only (model_copy — stored
   history and reloads are never affected). A single huge tool result can no
   longer alone blow the window; user/system messages are never truncated.

B. Token-budget hard-truncate fallback in compress_session: when partition
   no-ops but tokens exceed the threshold, drop oldest turns to num_ctx*0.5.
   _hard_truncate is now token-aware (was a fixed message-count floor that
   no-oped on <=6 messages even when huge). New would_compress() predicts
   compress_session's real outcome with no LLM call.

C. Honest CompressionStarted: _compression_events_midturn/_preturn emit it
   only after would_compress() confirms the partition (or token-budget
   fallback) can actually shrink the stored context — no more "compression"
   status with no ContextCompressed to follow.

Bonus: post-turn CompressionWorker now passes keep_recent_messages=
max(12, context_keep_recent*2), matching the midturn path, so a single long
autonomous turn compresses post-turn too (was always a no-op).

Tests (+14): would_compress agreement, token-budget fallback, token-aware
hard_truncate, build() truncation (preserves user, no mutation, head+tail),
agent no-CompressionStarted-when-nothing-to-compress, worker single-long-turn.

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

agent: cwd-aware memory fact filter for bounded autonomy ...

Long-term memory stored context-dependent path facts (e.g. "project_root
→ /home/.../navi-1") as global user facts. search_facts injected them into
any session, so when working in another project the agent was told "the
project root is navi-1" and drifted there.

When scope_boundary_enabled and a session cwd is set, _memory_facts_msg now
drops facts whose value is an absolute path outside the session cwd tree.
Facts are kept when working inside that path (then they are correct), and
non-path/relative facts always pass. Free flight stays reproducible by
toggling the flag off. No facts deleted, extractor untouched.

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

agent: bounded autonomy — scope boundary + observe-vs-act ...

navi_code had unwanted "free flight": an observe request ("look at a
directory") triggered the full Phase 3 plan with milestones + auto-todo,
and goal_anchoring then drove the agent to finish those steps, climbing
into sibling projects and executing milestone docs it found.

Two toggleable, default-off profile flags (on for navi_code):

- scope_boundary_enabled: injects a standing system message keeping the
  agent within the literally requested scope; forbids acting on
  discovered TODO/roadmap/milestone docs (report only).
- observe_skips_plan_enabled: Phase 1 classifies MODE: observe|act; an
  observe request skips Phase 2/3 — no multi-step plan, no auto-todo, no
  "execute step by step" prompt. The agent just gathers info and answers.
  Independent of force_plan (observe on the first message still skips).

Free flight stays reproducible by flipping both flags off.

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

Make Settings immutable (frozen=True) and fix all test mutations ...

- Add frozen=True to SettingsConfigDict in navi/config.py
- Convert model_validator to mode="before" since mode="after" cannot mutate frozen instances
- Replace all field-level monkeypatches in tests with whole-Settings object replacement
- Ensure cross-module settings consistency (content_store, session_files, share_file, content_publish, filesystem)

392 passed, 1 skipped

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Enhance native toolset and add persistent KV store ...

- Add PostgreSQL-backed KvStore (navi/store/) for session-scoped data.
- Migrate todo and scratchpad from in-memory dicts to KvStore.
- Filesystem: add copy, grep, diff actions; compress description.
- CodeExec: remove language param, expose working_dir in schema.
- ImageView: resize to 1024px JPEG + Content-Type guard for URLs.
- Memory list: return distinct categories instead of all facts.
- SSH: add scp action with upload/download support.
- Update CLAUDE.md (Postgres-only), docs/tools.md, add docs/store.md.
- Fix agent/planning/context_builder async signatures for todo helpers.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Clarify knowledge persistence prompts

Improve 3D modeling validation prompts

Bootstrap test suite — Phase 1 unit tests ...

- docs/testing.md: testing strategy, mock strategy, phase breakdown
- tests/conftest.py: autouse fixture to reset navi.config.settings per test
- tests/conftest_factory.py: FakeLLMBackend, FakeTool, make_profile, make_registry helpers
- tests/unit/core/test_events.py: wire serialization for all 15 event dataclasses
- tests/unit/core/test_compressor.py: should_compress, partition_messages, format_for_summary, compress_context
- tests/unit/core/test_registry.py: ToolRegistry, ProfileRegistry, BackendRegistry
- tests/unit/core/test_context_builder.py: system prompt caching, persona injection, goal anchor, iteration budget
- tests/unit/profiles/test_base.py: Pydantic model coercion, defaults, extra fields
- navi/core/context_builder.py: use module-level `import navi.config` instead of `from navi.config import settings` so tests can swap the singleton

59 tests passing.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>