feat(intelligence): build normalized graph and query snapshots

[szmyty]

Closes #7.

Outcome

Adds Observatory's first executable Repository Intelligence data-plane slice: a deterministic, provenance-aware repository graph/read model, fleet snapshot, page queries, and before/after comparison over the pinned Hygiene v1 projection.

What changed

• adds a dependency-free Python 3.11+ normalization/query package and observatory-intelligence CLI
• consumes exact egohygiene.repository-intelligence/v1 1.0.0-alpha.1 projections through a defensive boundary
• preserves canonical IDs, source URLs, represented commits, observation times, visibility, provenance, assertions, categorical confidence, freshness, redactions, and extensions
• derives Roadmap, Decisions, Journey, Now, Dependencies, Health, Releases, Work, and Search views
• derives transparent readiness, release-bounded history chapters, explicit blockers, next-ready work, and same-repository Compare deltas
• emits deterministic per-repository snapshots and a repository-context-preserving fleet snapshot
• publishes strict versioned envelopes for repository, fleet, view, and compare artifacts
• pins the merged Hygiene contract revision and checksums without copying validator ownership
• adds a byte-identical Hygiene complete-quest fixture plus an Observatory stale/inferred/unknown/blocked fixture
• checks in golden repository and fleet outputs so Relay and Holon can develop without live GitHub access
• records ADR-004, updates the ontology/system/architecture, and advances OBS-Q02 without claiming live provider ingestion

Ownership boundaries

This extends rather than duplicates #1 and #5:

• Build the normalized Repository Intelligence graph and query snapshots #7 owns shared identity/provenance indexing, deterministic queries, fleet composition, comparison, and offline fixtures
• Ingest the catalog and report repository maturity and conformance #1 still owns real catalog/repository evidence ingestion and maturity/conformance calculations
• Publish a Hygiene conformance dashboard for every repository #5 still owns the conformance-specific read model and organization/per-repository dashboard
• Hygiene owns the graph contract and vocabulary
• Egolint owns semantic validation
• Relay owns collection/orchestration/publication
• Holon owns rendering

The Hygiene Repository Intelligence contract remains alpha and its governing ADR is still proposed, so this pull request is intentionally draft.

Verification

• python3 -m unittest discover --start-directory "tests" --pattern "test_*.py" --verbose — 24 passed
• python3 "scripts/verify_fixtures.py" — 2 repository snapshots and 1 fleet snapshot reproduced exactly
• both source fixtures validated with Hygiene's pinned reference validator and vocabulary
• Python compile check — passed
• dependency-free wheel build — passed
• JSON contract/schema parsing — passed
• git diff --check — passed
• GitHub CI run 2 on Python 3.13 — install, tests, golden verification, and CLI smoke tests all passed

Delivery linkage

Roadmap-Step: OBS-Q02
ADR-Ref: ADR-004