feat(@fn_library): extract 2 components + improve 2 from Claude Design export

From: sources/frontend_designs/Ads Analytics Dashboard _standalone_.html

New components:
- funnel_chart_ts_ui — visualización de funnel de conversión con barras
  degradadas y tasa entre etapas como Badge semántico.
- heatmap_grid_ts_ui — matriz rows × cols con intensidad color-mix sobre
  el primary color. Genérica (day×hour, cohort, correlation...).

Improvements:
- alert_ts_ui v1.1.0 — añadidas variantes semánticas success, warning, info
  (antes: solo default y destructive).
- data_table_ts_ui v1.1.0 — prop opcional density: compact | cozy | roomy.
  No rompe API existente (default 'cozy' = comportamiento previo).

Barrel frontend/functions/ui/index.ts actualizado con los dos nuevos
exports y el type DataTableDensity.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/functions/ui/alert.md

@@ -3,10 +3,10 @@ name: alert
 kind: component
 lang: ts
 domain: ui
-version: "1.0.0"
+version: "1.1.0"
 purity: impure
-signature: "Alert(props: { variant?: 'default' | 'destructive' }): JSX.Element"
-description: "Alerta accesible con variantes default y destructive. Mantine Alert con slots para título, descripción y acción."
+signature: "Alert(props: { variant?: 'default' | 'destructive' | 'success' | 'warning' | 'info' }): JSX.Element"
+description: "Alerta accesible con 5 variantes semánticas (default, destructive, success, warning, info). Mantine Alert con slots para título, descripción y acción."
 tags: [alert, feedback, component, ui, notification, mantine]
 uses_functions: []
 uses_types: []
@@ -21,13 +21,13 @@ test_file_path: ""
 file_path: "frontend/functions/ui/alert.tsx"
 props:
   - name: variant
-    type: "'default' | 'destructive'"
+    type: "'default' | 'destructive' | 'success' | 'warning' | 'info'"
     required: false
-    description: "Variante visual"
+    description: "Variante visual semántica."
 emits: []
 has_state: false
 framework: react
-variant: [default, destructive]
+variant: [default, destructive, success, warning, info]
 source_repo: "https://gitea-dgg044oo04woo4ggcsws4gk0.organic-machine.com/Bl4cksmith/Frontend_Library"
 source_license: "MIT"
 source_file: "frontend/src/components/ui/alert.tsx"