Add DD-078 Slice 1A obligation truth model

[larimonious]

Summary

Adds the narrow, app-independent Intent truth foundation needed before any test runner or evidence report:

• source-located explicit IDs for features, scenarios, and outcomes;
• compatibility-derived IDs that remain visibly rename/reorder-sensitive;
• hierarchical compatibility identity that preserves exact parent IDs and prevents cross-scope collisions;
• one obligation per behavioral scenario outcome, with fail-closed cardinality checks;
• non-vacuous feature truth (zero outcomes != verified);
• legacy test: cases remain visible and prevent feature verification until represented as stable obligations;
• explicit documentation-only features with required rationale;
• typed, referentially checked evidence-to-obligation and canonical obligation-to-feature-to-scenario relationships;
• parser-owned identity sidecars that preserve the existing public IntentFile/Feature/Scenario AST shapes;
• externally read-only truth and evidence records, leaving validated ingestion authority to a later slice;
• duplicate or contradictory in-memory identity state fails closed in feature and coverage predicates;
• orthogonal declaration, linkage, binding, executability, disposition, freshness, and assertion-resolution dimensions.

Intent / IAL compatibility

• Existing parsing remains in compatibility mode by default.
• Durable cross-run evidence must opt into strict parsing and explicit IDs.
• Legacy Constraint: scenarios remain visible in the parser AST but do not interpret verification-like IDs, become obligations of the preceding feature, alter its identity/metadata/tests, trigger strict-ID requirements, or invalidate a documentation-only feature.
• Markdown headings, separators, and named declarations close prior parser-section state before enabling their own; blank titles, Constraint:, technical bindings, test-data/invariant sections, and legacy test: blocks cannot swallow or mutate later behavior.
• Strict orphan scenarios, outcomes, and legacy tests are rejected with source locations.
• Repeated explicit IDs on one declaration fail with both source locations instead of silently replacing identity; scenario IDs must precede identity-bearing outcomes.
• Legacy outcome prose beginning with id: remains prose unless it uses the explicit id: outcome.*; statement form.
• Component, feature, scenario, and outcome compatibility IDs occupy deterministic hierarchical scopes.

Deliberate non-goals

This PR does not add or freeze:

• a native .tnt unit-test declaration or runner;
• execution, setup, fixture, resource, or cleanup semantics;
• a report/JSON serialization contract, schema, renderer, threshold, or exit policy;
• project manifests, discovery policy, protected CI, purity, providers, or application-specific assumptions;
• replacement of glossary-driven IAL unit tests.

Those decisions require the revised testing DD and an end-to-end ntnt test vertical slice. PRs #179 and #180 are drafts while that architecture is reconsidered.

Validation

• 54/54 focused truth tests (40 integration + 14 private model-invariant tests)
• 2,015/2,015 non-conflicting nextest tests
• 2/2 fixed-port Intent checks run serially
• DD-078 plan tests
• doctests
• dev-release build
• rustfmt and git diff --check

cargo clippy --all-targets --all-features remains blocked by pre-existing repository warnings/errors outside this diff, including existing approximate-constant test fixtures.

[greptile-apps]

Greptile Summary

This PR implements DD-078 Slice 1A: stable verification identity and an in-memory truth model for obligation tracking. Two previously flagged parser bugs (the missing !in_constraint guard on the verification: handler and the component id: overwrite by a constraint id:) are both fixed, with dedicated regression tests.

• Adds IdentifiedIntent, VerificationTruth, and orthogonal truth dimensions (declaration, linkage, binding, executability, disposition, freshness, assertion-resolution) with tamper-resistant canonical snapshots that detect caller-side mutation of the obligation denominator.
• Introduces StableId with strict and compatibility-derived modes, source-located warnings/errors for missing or duplicate IDs, and the in_constraint flag that isolates legacy Constraint metadata from feature verification state throughout the parser.
• 17 fixture files and 1,260-line integration test suite cover duplicate IDs, malformed IDs, constraint boundary isolation, documentation-only semantics, and canonical-topology tamper proofing.

Confidence Score: 5/5

Safe to merge. The parser refactor is well-isolated, all previously flagged constraint boundary issues are fixed with targeted regression tests, and the new truth model's tamper-detection design prevents callers from silently zeroing the obligation denominator.

Both constraint boundary parser bugs that were flagged on earlier review rounds are now guarded correctly — !in_constraint on the verification: handler and on the component id: handler — and each has a dedicated regression test. The new VerificationTruth model's canonical snapshot design means any caller-side mutation causes all truth predicates to fail closed. The 1,260-line integration suite and 17 fixture files give strong coverage. No new defects were found in this pass.

Files Needing Attention: No files require special attention.

Important Files Changed

Filename	Overview
src/intent.rs	Large refactor adding ParsedFeature/ParsedScenario wrappers, in_constraint flag, per-line numbering, and IdentifiedIntent. Both previously flagged constraint boundary bugs are correctly guarded; comprehensive tests cover all regression paths.
src/verification/ids.rs	New module: StableId, IdMode, validate_id, and slug. Explicit IDs are validated; compatibility-derived IDs use slug()-capped labels and embed the full parent value for uniqueness. Logic is correct and well-tested.
src/verification/model.rs	New module: VerificationTruth with orthogonal dimension enums, canonical topology tamper-detection, and coverage queries. All truth predicates fail closed; linkage and behavioral evidence remain orthogonal.
tests/verification_truth_tests.rs	1,260-line integration suite covering strict/compat ID modes, constraint boundary isolation, documentation-only semantics, canonical topology tampering, and legacy AST backward-compatibility surface.
src/verification/mod.rs	New module root re-exporting the Slice 1A public API; clean and minimal.
src/lib.rs	One-line addition exposing the verification module.

_{Reviews (4): Last reviewed commit: "fix: narrow Intent obligation identity s..." | Re-trigger Greptile}