…scaping

Two bugs in tests/integration_test.rs caused 2 of 9 integration tests to
fail (the unit tests were unaffected).

1. Prefix mismatch — codegen emits identifiers prefixed `verisimdb_`
   (see src/codegen/overlay.rs). The integration tests asserted
   substring presence of `verisim_…` which is not a substring of
   `verisimdb_…`. Replaced 11 occurrences in tests/integration_test.rs.

2. Windows path escaping — test_end_to_end_file_workflow interpolates
   `schema_path.display()` into a TOML basic string with `"…"`. On
   Windows the path contains backslashes which TOML treats as escapes,
   producing a malformed manifest and an unwrap-on-Err. Switched the
   embedded path to a TOML literal string (single quotes) which
   suppresses escape interpretation.

Verified: cargo test now reports 26 + 26 + 9 = 61 tests, 0 failed.

Closes #8

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

Per ADR-0001 the canonical octad is concerns
(Data/Metadata/Provenance/Lineage/Constraints/AccessControl/Temporal/
Simulation), not modalities. The previous README led with a modalities
table the codebase no longer supported.

README.adoc rewrites:

- Replace the "Eight Modalities" table with an "Eight Concerns" table
  whose rows match `OctadDimension` enum, OctadConfig fields, and the
  emitted sidecar tables.
- Reframe the eight cross-modal drift categories under Constraints
  (they are symptoms observed by Constraints when Data, Metadata, and
  active Tier 2 overlays disagree). Note explicitly that each category
  still needs a computable definition.
- Tier 1 narrative reorganised around the five Tier 1 concerns
  (Provenance, Temporal, Constraints, Lineage, AccessControl).
- Tier 2 retains modalities but as overlay representations, not as
  "the octad".
- Add a "Related repos" section linking verisimdb-data.
- Add an "ABI" section pointing at src/interface/abi/ and
  src/interface/ffi/ where the Idris2 and Zig stubs actually live.
- Cite ADR-0001 and ADR-0002 inline.

ROADMAP.adoc rewrites:

- Phase 0 marked complete with accurate evidence (ABI types exist in
  three languages; codegen scaffolding ships).
- Phases reordered to match the bottom-up plan: SQLite Tier 1 MVP
  first (cheapest end-to-end), then PostgreSQL, then multi-backend,
  then Constraints/Drift, then AccessControl/Lineage, then Tier 2
  modality overlays, then Simulation, then VCL-total integration,
  then production hardening, then ecosystem.
- Each phase phrased in concerns/modality terms consistent with
  ADR-0001.

Closes #20

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

…r commit

The `rust-ci.yml` lane already runs `cargo check + clippy + fmt` (job
`check`) and `cargo test --all-targets` (job `test`, depends on `check`).
That is exactly what V-L3-A2 asked for — the previous mega-list
incorrectly claimed no cargo-test gate existed.

Real improvement this commit lands:

- Add a `concurrency` block at workflow level so push storms cancel
  older queued runs instead of queueing for minutes. Group keyed on
  `github.ref` so concurrent PR pushes serialize per-PR but parallel
  to main.

Verified locally:
- `cargo fmt --all -- --check` clean
- `cargo clippy --all-targets -- -D warnings` clean
- `cargo test` reports 35 tests (26 lib + 9 integration), 0 failed

The cargo-test gate becomes a required check when branch protection
is configured to require Rust CI / Cargo test — that is a repo
settings change, not a workflow change.

Closes #9

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