Remove references to "v4" throughout the code and documentation

.github/instructions/error-handling.instructions.md

@@ -7,13 +7,13 @@ applyTo: 'src/transcription/**/*.py'
 
 Primary references:
 
-- `docs/ver4/error_handling_v4.md`
+- `docs/error_handling.md`
 - `docs/invariant/error_handling.md`
-- `docs/ver4/requirements_v4.md`
+- `docs/requirements.md`
 
 ## Taxonomy and Categories
 
-Use category-driven semantics aligned to canonical V4 policy:
+Use category-driven semantics aligned to canonical policy:
 
 - `validation`
 - `not_found`
@@ -91,7 +91,7 @@ Required internal -> canonical mapping:
 
 If taxonomy, retries, or envelope semantics change:
 
-1. Update canonical docs (`docs/ver4/error_handling_v4.md`, and invariant docs if needed).
+1. Update canonical docs (`docs/error_handling.md`, and invariant docs if needed).
 2. Update tests in the same change.
 3. Update related instruction/skill references.
-4. If change affects persisted status/category fields, update `docs/ver4/schema_v4.md` when applicable.
+4. If change affects persisted status/category fields, update `docs/schema.md` when applicable.

.github/instructions/services.instructions.md

@@ -120,18 +120,18 @@ Atomicity rules:
 - Terminal state (`TRANSCRIBED` or `FAILED`) and transcript row changes must succeed or roll back together.
 - Retry persistence (`QUEUED` + retry increment + error detail) must succeed or roll back together.
 
-## V4 Contract Alignment
+## Contract Alignment
 
-- Treat `docs/ver4/` as the active architecture and requirements baseline.
-- Legacy V4 revision trees are out of scope for active implementation decisions and must not be referenced as authoritative service guidance.
-- Treat `src/transcription/db/models.py` as runtime schema ground truth and `docs/ver4/schema_v4.md` as the field-accurate contract mirror.
+- Treat `docs/` as the active architecture and requirements baseline.
+- Legacy revision trees are out of scope for active implementation decisions and must not be referenced as authoritative service guidance.
+- Treat `src/transcription/db/models.py` as runtime schema ground truth and `docs/schema.md` as the field-accurate contract mirror.
 - `Job.status` success path is `TRANSCRIBED`.
 - `JobSource.status` is queue/projection state only (`PENDING`, `TRANSCRIBED`, `FAILED`, `CANCELLED`).
 - Source ingest may normalize media before persistence; persisted bytes/hash are canonical for processing and provenance.
 - `ExecutionAttempt` is append-only evidence history; do not mutate historical attempt rows in runtime code.
 - `Source.raw_transcription` is a projection, not authoritative history.
 - Service/UI read paths that touch relationships must be eager-loaded for `lazy="raise"` compatibility.
-- If model fields, enums, constraints, indexes, or relationship-loading semantics change, update `docs/ver4/schema_v4.md` in the same change.
+- If model fields, enums, constraints, indexes, or relationship-loading semantics change, update `docs/schema.md` in the same change.
 - If `Settings` fields or defaults change in `src/transcription/config.py`, update `.env.example` in the same change so keys/defaults remain synchronized and no stale settings remain documented.
 
 # Service Composition

.github/instructions/ui.instructions.md

@@ -69,10 +69,10 @@ Prohibited patterns:
 - Manual URL construction from raw `Path` values in pages/components.
 - User-facing payloads containing local absolute paths.
 
-## V4 Contract Alignment
+## Contract Alignment
 
-- Treat `docs/ver4/` as the active baseline.
-- Resolve lifecycle and status semantics against `src/transcription/db/models.py` and `docs/ver4/schema_v4.md`; do not introduce alternate status labels or implied legacy states in UI behavior.
+- Treat `docs/` as the active baseline.
+- Resolve lifecycle and status semantics against `src/transcription/db/models.py` and `docs/schema.md`; do not introduce alternate status labels or implied legacy states in UI behavior.
 - Use status vocabulary exactly as modeled (`queued`, `processing`, `transcribed`, `partial_success`, `failed`; and `pending`, `transcribed`, `failed`, `cancelled`).
 - Print/export media flows must use record-validated routes; direct local filesystem paths are prohibited.
 - If lifecycle wording/behavior changes, update corresponding `docs/ui/pages/*.md` contracts in the same change.