Edge building excludes constant nodes from dependency graph

[carlos-alm]

Bug

codegraph where BUILTIN_RECEIVERS -T --json returns empty results, and fn-impact reports 0 dependents — yet grep confirms 3 active consumers in core source files (incremental.js, build-edges.js).

Root Cause

The JS extractor does correctly extract export const declarations as constant-kind nodes and they are inserted into the nodes table. However, the edge-building stage in src/domain/graph/builder/stages/build-edges.js (line 31) excludes them from the node lookup:

SELECT id, name, kind, file, line FROM nodes
WHERE kind IN ('function','method','class','interface','struct','type','module','enum','trait')

'constant' is not in this list. As a result:

• Constants exist in the DB but are never loaded into nodesByName / nodesByNameAndFile
• No import/dependency edges are created for them
• They are invisible to where, fn-impact, query, roles, and all other graph queries

Impact

• codegraph roles --role dead misclassifies constants as dead (0 fan-in because no edges exist)
• codegraph where can't find them at all
• codegraph fn-impact reports 0 dependents for actively-used constants
• Any downstream tooling (e.g. automated dead-code cleanup) that trusts codegraph data will incorrectly target these symbols for removal

Affected Symbols (examples from this repo)

• BUILTIN_RECEIVERS — export const in src/domain/graph/builder/helpers.js, used in 3 source files
• BATCH_CHUNK — export const in same file, actively imported
• MAX_COL_WIDTH — export const, used in presentation layer

Fix

Add 'constant' to the WHERE kind IN (...) clause in build-edges.js line 31, so constants participate in edge resolution like any other symbol.