Fix duplicate config source registration in ConfigSourceRegistry

Deduplicate by name in register() to prevent accumulation when both
B2CPluginManager and oclif hook paths discover the same plugins.

Author: clavery

.changeset/deduplicate-config-source-registry.md

@@ -0,0 +1,5 @@
+---
+'@salesforce/b2c-tooling-sdk': patch
+---
+
+Fix duplicate config source registration in `ConfigSourceRegistry` when multiple discovery paths find the same plugins

packages/b2c-tooling-sdk/src/config/config-source-registry.ts

@@ -67,6 +67,7 @@ export class ConfigSourceRegistry {
    * @param source - The config source to register
    */
   register(source: ConfigSource): void {
+    if (this.sources.some((s) => s.name === source.name)) return;
     this.sources.push(source);
   }
 

packages/b2c-tooling-sdk/test/config/config-source-registry.test.ts

@@ -29,6 +29,15 @@ describe('config/config-source-registry', () => {
     expect(registry.getSourceNames()).to.deep.equal(['s1', 's2']);
   });
 
+  it('register() silently ignores duplicate source names', () => {
+    const registry = new ConfigSourceRegistry();
+    registry.register(createStubSource('s1'));
+    registry.register(createStubSource('s1'));
+
+    expect(registry.size).to.equal(1);
+    expect(registry.getSourceNames()).to.deep.equal(['s1']);
+  });
+
   it('unregister() removes an existing source by name', () => {
     const registry = new ConfigSourceRegistry();