feat: semantic search with Qdrant + Ollama embeddings

- Add SemanticSearchService with embed() + searchQdrant() methods
- Add GET /api/search/semantic endpoint (?q=query&k=5)
- Wire SemanticSearchService into router and cmd/server/main.go
- Add SemanticSearch React page with results + similarity scores
- Add 'Semantic Search' nav link in App.tsx
- Add unit tests with mocked Ollama + Qdrant HTTP servers (4 tests, all passing)
- Add GitHub issue templates (bug report, feature request)
- Add pull request template

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,57 @@
+name: Bug Report
+description: Report something that is broken or not working as expected
+labels: ["bug"]
+title: "[Bug] "
+body:
+
+- type: markdown
+  attributes:
+    value: |
+      ## Bug Description
+      Describe what broke and what you expected to happen.
+
+- type: textarea
+  id: repro
+  attributes:
+    label: Steps to Reproduce
+    placeholder: |
+      1.
+      2.
+      3.
+  validations:
+    required: true
+
+- type: textarea
+  id: expected
+  attributes:
+    label: Expected Behavior
+    placeholder: What should happen instead.
+
+- type: textarea
+  id: actual
+  attributes:
+    label: Actual Behavior
+    placeholder: What actually happens.
+
+- type: input
+  id: version
+  attributes:
+    label: UMM Version / Commit
+    placeholder: e.g., v2.0 or git commit hash
+
+- type: textarea
+  id: logs
+  attributes:
+    label: Relevant Logs
+    description: Paste any error messages or relevant log lines
+
+- type: textarea
+  id: env
+  attributes:
+    label: Environment
+    description: OS, Docker version, database version, etc.
+    placeholder: |
+      - OS:
+      - Docker:
+      - PostgreSQL:
+      - Go (if running locally):