chore: prepare the authorized 0.7.0 release

[yia-mw-agent]

Summary

• Identify the tree as 0.7.0, superseding the unpublished 0.6.1 candidate. PyPI and GitHub Releases remain 0.6.0 until Captain tags and publishes.
• Update project metadata, module fallback, the local uv.lock package entry, version-sensitive tests/examples, and current install/version docs.
• Consolidate changes since v0.6.0 into a 0.7.0 candidate changelog with issue/PR links and migration notes. Frozen issue Measure and reduce MCP context overhead without losing the learning workflow #104 measurement artifact and unrelated lock versions (including ollama 0.6.1) are unchanged.

Motivation

Owner-authorized 0.7.0 release preparation from current main. Captain owns tagging, workflow approval, publication, and post-publication verification.

Closes #117

Changes

• pyproject.toml, src/fava_trails/__init__.py fallback, and local uv.lock package entry report 0.7.0
• Version-sensitive tests (test_packaged_mcp, test_retrieval_baseline) expect 0.7.0; upgrade-from-0.6.0 gate remains
• Changelog, README, setup/runtime/FAQ/one-pager/baseline docs describe the 0.7.0 candidate as unpublished
• Frozen issue_104_tested_release.json stays 0.6.1; ollama lock stays 0.6.1

Test Plan

• Loaded package/module version is 0.7.0 (importlib.metadata + fava_trails.__version__)
• uv run pytest tests/test_retrieval_baseline.py tests/test_runtime_info.py tests/test_dependency_constraints.py
• uv run pytest -v — 1056 passed in this PATH; 5 test_jj_backend tests fail only when jj is missing from PATH, pass with ~/.local/bin/jj (0.28.0)
• tests/test_packaged_mcp.py::test_candidate_artifacts_support_fresh_install_and_upgrade_from_0_6_0 passed (wheel, sdist, 0.6.0→candidate)
• Captain independently reviews current exact head before merge
• Existing release workflow still validates built wheel/sdist/native MCP and upgrade from 0.6.0 before publication (owner-gated; this PR does not tag or publish)

Notes for Reviewers

• Worker did not tag, publish, merge, or change release environment policy, secrets, default provider, or real trails data.
• Five-real-session Rich Views acceptance was waived; changelog does not claim those sessions happened.
• Canonical metadata pr_url for Kanban closeout is this PR.

[timeleft--]

Independent Captain review of exact head 878b265ff570a1b950dd248810772b14959d341e: clean, no actionable findings.

The 13-file diff changes only release version metadata, candidate documentation/changelog, and version-sensitive test expectations. The local FAVA lock entry changes to 0.7.0; unrelated dependencies and the frozen issue #104 0.6.1 measurement artifact remain intact. Upgrade/identity/lexical-search/secret-preflight limitations stay explicit, and the code makes no release-publication or real-session claim before those events.

Independent verification in a separate Captain worktree: uv sync --frozen; full uv run pytest -q 1,061 passed in 244.23 seconds, including packaged wheel/sdist/native MCP and 0.6.0 upgrade tests; focused Ruff passed; git diff --check passed. fava-trails version reports package/module/handshake 0.7.0, MCP SDK 2.2.0. All nine current GitHub checks passed, including both JJ 0.28.0 and 0.45.1 matrices.

Owner September 13 approval authorizes 0.7.0 publication. Merge is safe for this exact reviewed head; immutable tagging and the existing gated release workflow remain separate subsequent steps.