feat(intent): posts: stage 2 - handler template + resolver/renderer

[delchev]

What

Stage 2 of posts: (event-driven row posting; stage 1 model+glue merged as #6405). Builds the
generated handler on the proven postings: skeleton, flattened (no header document - N rows
straight into the target).

Changes

• buildPosts resolver - the full glue descriptor: trigger (event: = create |
  numeric status seed id → the -created/-transitioned topic + a status guard), the composition-child
  coordinates for forEach (itemsEntity/Fk/perspective), target coordinates, the idempotentBy
  back-reference, and the rendered set: assignments.
• postSetExpr renderer - each set: value → a Java expression over source/item: item copy
  (item.X), null-safe negation (-item.X), source copy (source.X), integer constant, quoted string.
• Posts.java.template - a MessageHandler on the source's -transitioned/-created topic that,
  idempotent by the back-reference, emits one target row per forEach item (or one per source)
  through the target's generated repository.
• Registered in the events template.js (collection: posts) + a generateUtils.js case "posts"
  (maps/sanitizes the glue → template params). glue.put("posts", ...) wires it into the .glue.

Authoring

posts:
  - name: goodsIssueLedger
    forEntity: GoodsIssue
    event: 2                 # a status seed id (fires on -transitioned into it), or `create`
    forEach: items           # the composition child; omit = one row per source
    into: StockMovement
    idempotentBy: GoodsIssue  # back-reference FK; skip if target rows already exist
    set:
      Product:  item.Product
      Quantity: "-item.Quantity"    # null-safe negate
      Direction: 2                  # constant
      Store: source.Store           # source copy

Verification

engine-intent 217/217. GluePostsTest asserts the resolved descriptor end-to-end: event: 2 →
status guard on the Status property; GoodsIssueItem/GoodsIssue composition child; StockMovement
target + GoodsIssue back-ref; and the rendered Java exprs (incl.
item.Quantity == null ? null : item.Quantity.negate()). The handler template mirrors the proven
Posting.java.template.

Follow-up (stage 3)

Generation/boot verification of the emitted handler (compiles + posts identical rows) and adoption in
kf-mod-inventory (retire the 6 *PostDelegates + the adjustment poster). event: numeric-id →
optional status-name resolution is a nicety.

🤖 Generated with Claude Code