feat(schema): body nodes and parameters carry their id in analysis.json (python #180 parity) #164

Problem

codeanalyzer-python 1.4.1 (#180, design in its #176) stamps an id on every body node and every
parameter in analysis.json: body[<local>].id = <callable-id>@<local> — the same value the Neo4j
projection merges the body node on — and parameters[i].id = <callable-id>@formal_in:<i>, the L4
formal_in vertex that carries the parameter, emitted as a forward reference below level 4. The
shared vocabulary.md was updated to say so.

TypeScript emits neither. A JSON consumer that wants to name a statement or a parameter has to
recompose the join key itself, and the composition rule lives in TWO private copies here
(fq in src/build/neo4j/project.ts and again in src/dataflow/attach.ts).

Scope boundary

Additive schema fields and one shared helper. No Neo4j label/relationship change — :TSBodyNode
already carries id as its merge key; parameters are not graph nodes. SCHEMA_VERSION stays
2.0.0 (#144).

Goals

• globalOrdinal(callableId, localKey) in src/schema/ids.ts — the single definition of the
  body-node id; project.ts and attach.ts use it instead of their private fq
• stampBodyIds(c): id on every body{} node and parameters[i].id = <id>@formal_in:<i>,
  idempotent, called by each body emitter after it writes (L1 populateL1Body, L3 emitL3,
  L4 after emitL4)
• Two-projection agreement tests, mirroring python's: L3 body-node ids equal the projected
  :TSBodyNode keys; L4 parameter ids equal the @formal_in:<i> vertex ids, in list order
• .claude/SCHEMA_DECISIONS.md entry

Caveats and known risks

• Per-run, like every id: the cache must stay id-free. saveCache runs before finalizeAnalysis,
  so stamping onto tree nodes there is safe — the test that pins it is the existing cache-shape gate
• Monotonicity: id on an L1 call node must be byte-identical at L2–L4 (the key never changes;
  only callee does)

Definition of done

• The two agreement tests pass; schema-v2 monotonicity gate still passes with id present
• bun test green; container tests run (projection touched)