refactor(scripts): move 7 code_path_audit files from src/ to scripts/code_path_audit/

The 7 code_path_audit*.py files (2604 lines total) are pure static
analysis tools. They do AST traversal of src/, no intrusive profiling,
no runtime markers. They were inlaid with src/ but only import:
- src.result_types (the Result[T] convention type)
- each other (the 6 siblings)

After the move:
- src/ is now pure application code; line-count audit metrics are clean
- scripts/code_path_audit/ is a new namespace-isolated subdir per
  AGENTS.md 'scripts are namespace-isolated by directory' rule

TIER-3 READ AGENTS.md + conductor/workflow.md + conductor/edit_workflow.md
+ conductor/code_styleguides/code_path_audit.md + the 7 files before
this commit.

Changes:
- 7 files moved: src/code_path_audit*.py -> scripts/code_path_audit/
- 7 files updated: internal imports rom src.code_path_audit_X ->
  rom code_path_audit_X (siblings in same subdir)
- 7 files updated: add sys.path.insert(0, str(Path(__file__).resolve().parents[2] / 'src'))
  to find src.result_types when run standalone
- 5 test files updated: rom src.code_path_audit -> rom code_path_audit
  + sys.path setup to find the new subdir
- 6 throwaway scripts in scripts/tier2/artifacts/ updated: import path
  + sys.path setup (parents[3] / 'src' + parents[3] / 'scripts' / 'code_path_audit')
- 2 styleguide/spec references updated: conductor/code_styleguides/code_path_audit.md
  + conductor/tracks/code_path_audit_20260607/spec_v2.md
- 1 meta-audit docstring updated: scripts/audit_code_path_audit_coverage.py
- 1 type registry entry deleted: docs/type_registry/src_code_path_audit.md
  (the type is no longer in src/)
- 1 type registry index updated: docs/type_registry/index.md (22 files, was 23)

Verification:
- 7/7 audit gates pass --strict (weak_types 102<=112, type_registry 22 files,
  main_thread_imports OK, no_models_config_io OK, code_path_audit_coverage 0
  violations, exception_handling 0 violations, optional_in_3_files 0 violations)
- 6/6 test files pass: test_code_path_audit, test_code_path_audit_integration,
  test_code_path_audit_phase78, test_code_path_audit_phase89,
  test_code_path_audit_ssdl_behavioral, test_metadata_nil_sentinel
- src/ line count: 29997 lines (down from 32621 = -2624 lines)
- scripts/code_path_audit/ line count: 2620 lines

conductor/code_styleguides/code_path_audit.md

@@ -2,7 +2,7 @@
 
 > **Status:** Active convention as of 2026-06-22. Established by the `code_path_audit_20260607` v2 track.
 
-This styleguide codifies the contract for `src/code_path_audit.py` v2 and the 6 input audit scripts it consumes. Companion to `data_oriented_design.md`, `error_handling.md`, `type_aliases.md`, and `agent_memory_dimensions.md`.
+This styleguide codifies the contract for `scripts/code_path_audit/code_path_audit.py` v2 and the 6 input audit scripts it consumes. Companion to `data_oriented_design.md`, `error_handling.md`, `type_aliases.md`, and `agent_memory_dimensions.md`.
 
 ## The 5 Conventions
 
@@ -10,7 +10,7 @@ This styleguide codifies the contract for `src/code_path_audit.py` v2 and the 6
 
 Every `AggregateProfile` (the central artifact) has 15 fields (14 required + 1 default): `name`, `aggregate_kind`, `memory_dim`, `producers`, `consumers`, `access_pattern`, `access_pattern_evidence`, `frequency`, `frequency_evidence`, `result_coverage`, `type_alias_coverage`, `cross_audit_findings`, `decomposition_cost`, `optimization_candidates`, `is_candidate` (plus `mermaid` and `markdown` with defaults). The `is_candidate: bool` flag distinguishes the 3 placeholder aggregates (`ToolSpec`, `ChatMessage`, `ProviderHistory`) from the 10 real aggregates.
 
-The custom postfix `.dsl` output is the canonical artifact: each section is a self-contained tagged record (flat, streamable, tag-scannable). The 14 new v2 DSL words: `kind`, `mem-dim`, `fn-ref`, `access-pattern`, `ap-evidence`, `frequency`, `freq-evidence`, `result-coverage`, `type-alias-coverage`, `cross-audit-finding`, `cross-audit-findings`, `decomp-cost`, `opt-candidate`, `is-candidate`. Arity table in `src/code_path_audit.py:DSL_WORD_ARITY_V2`.
+The custom postfix `.dsl` output is the canonical artifact: each section is a self-contained tagged record (flat, streamable, tag-scannable). The 14 new v2 DSL words: `kind`, `mem-dim`, `fn-ref`, `access-pattern`, `ap-evidence`, `frequency`, `freq-evidence`, `result-coverage`, `type-alias-coverage`, `cross-audit-finding`, `cross-audit-findings`, `decomp-cost`, `opt-candidate`, `is-candidate`. Arity table in `scripts/code_path_audit/code_path_audit.py:DSL_WORD_ARITY_V2`.
 
 ### 2. The 4 decomposition directions
 
@@ -21,7 +21,7 @@ For each aggregate, the audit computes a `DecompositionCost` (8 fields: `current
 - **`hold`** - current shape is correct; default for `frozen + whole_struct` (the ideal shape).
 - **`insufficient_data`** - access pattern is `mixed` or frequency is `unknown`; needs runtime profiling per pipeline.
 
-The 4-direction logic is in `src/code_path_audit.py:recommended_direction()`. The savings estimates are heuristic (calibrated by `pipeline_runtime_profiling_20260607`); use as ranking input, not as actual savings.
+The 4-direction logic is in `scripts/code_path_audit/code_path_audit.py:recommended_direction()`. The savings estimates are heuristic (calibrated by `pipeline_runtime_profiling_20260607`); use as ranking input, not as actual savings.
 
 ### 3. The override file format
 
@@ -39,7 +39,7 @@ The file is optional. Missing file = empty overrides (the canonical mappings + h
 
 ### 4. The 4 mem dim classification rules
 
-`MemoryDim` is a 7-value Literal: `curation`, `discussion`, `rag`, `knowledge`, `config`, `control`, `unknown`. The classification precedence (per `src/code_path_audit.py:classify_memory_dim()`): overrides > canonical mappings > file-of-origin heuristic > `unknown`.
+`MemoryDim` is a 7-value Literal: `curation`, `discussion`, `rag`, `knowledge`, `config`, `control`, `unknown`. The classification precedence (per `scripts/code_path_audit/code_path_audit.py:classify_memory_dim()`): overrides > canonical mappings > file-of-origin heuristic > `unknown`.
 
 - **`curation`**: per-file structural (FileItem, FileItems, ContextPreset).
 - **`discussion`**: per-turn conversational (Metadata, CommsLog, History, ChatMessage).