feat(impact): cross-language blast-radius coverage (22 languages + 14 frameworks) (#708)

Completes the cross-file dependency graph behind impact / affected / explore across all 22 supported languages and 14 web frameworks, validated on real-world repos (measured fair-coverage table added to the README). Per-language resolution + framework resolvers/synthesizers (Lua/Luau require, Shopify OS 2.0 Liquid sections, Delphi forms, Rust cross-module + Rocket macros, Swift Fluent, SvelteKit/Nuxt loader/component conventions, RN/Expo bridges). 0 cross-family false edges, full suite green (1187 passed). See #708.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/db/queries.ts

@@ -1351,6 +1351,52 @@ export class QueryBuilder {
     return rows.map(rowToEdge);
   }
 
+  /**
+   * Distinct file paths that DEPEND ON `filePath`: every file containing a
+   * symbol with a cross-file edge (any kind except `contains`) into a symbol
+   * of this file. This is the file-level projection of the symbol dependency
+   * graph and the basis for blast-radius / `affected` test selection.
+   *
+   * It deliberately does NOT restrict to `imports` edges. In this graph an
+   * `imports` edge connects a file to its own local import declarations
+   * (it is always same-file), so an imports-only lookup returns zero
+   * cross-file dependents for every file. The real cross-file dependency
+   * signal is the resolved call/reference graph — calls, references,
+   * instantiates, extends, implements, overrides, type_of, returns,
+   * decorates — exactly what {@link GraphTraverser.getImpactRadius} traverses.
+   * `contains` is excluded: a parent containing a symbol does not *depend* on
+   * it. One indexed query (idx_nodes_file_path + idx_edges_target_kind).
+   */
+  getDependentFilePaths(filePath: string): string[] {
+    const sql = `SELECT DISTINCT src.file_path AS fp
+      FROM edges e
+      JOIN nodes tgt ON tgt.id = e.target
+      JOIN nodes src ON src.id = e.source
+      WHERE tgt.file_path = ?
+        AND e.kind != 'contains'
+        AND src.file_path != ?`;
+    const rows = this.db.prepare(sql).all(filePath, filePath) as Array<{ fp: string }>;
+    return rows.map((r) => r.fp);
+  }
+
+  /**
+   * Distinct file paths that `filePath` DEPENDS ON — the inverse of
+   * {@link getDependentFilePaths}: every file containing a symbol that a
+   * symbol of this file has a cross-file edge into. Same edge-kind rules
+   * (all kinds except `contains`); same reason imports-only is insufficient.
+   */
+  getDependencyFilePaths(filePath: string): string[] {
+    const sql = `SELECT DISTINCT tgt.file_path AS fp
+      FROM edges e
+      JOIN nodes src ON src.id = e.source
+      JOIN nodes tgt ON tgt.id = e.target
+      WHERE src.file_path = ?
+        AND e.kind != 'contains'
+        AND tgt.file_path != ?`;
+    const rows = this.db.prepare(sql).all(filePath, filePath) as Array<{ fp: string }>;
+    return rows.map((r) => r.fp);
+  }
+
   // ===========================================================================
   // File Operations
   // ===========================================================================