Restore complete OSBAPI parameter-schema editing for service instances

[nabramovitz]

Restores complete OSBAPI (JSON Schema) parameter editing on the service-instance create/update form. The Tailwind/ngrx migration had replaced the AJSF-based schema form with a flat stub that dropped nesting, arrays, and composition; this brings that capability back, signal-native, with Monaco for the raw-JSON view.

Closes #5488.

What's in it

• A new recursive, signal-native SchemaWidgetRenderer (selector json-schema-form) covering the full JSON Schema Draft-4 vocabulary: object nesting, scalars (incl. format such as password), enum selects, arrays (add/remove/reorder), multi-select (uniqueItems enum arrays), oneOf/anyOf (including scalar branches), allOf, $ref/$defs, an additionalProperties map editor, tuples, and an unknown-node JSON fallback so nothing is unrenderable.
• The two-view (Form / JSON) editor is kept; the JSON view now uses Monaco fed the plan schema.
• Validation is advisory: only unparseable JSON blocks submission; schema mismatches (type, required, etc.) surface as inline warnings — the broker remains the final authority (e.g. integer 5 vs string "5" warns but does not block).
• If a plan's schema is too malformed to render as a form, the editor falls back to the JSON view with the schema's title/description and a short guidance message, preserving any entered params.
• Removes the flat stub (TailwindJsonSchemaForm*) and its dead service; the Kubernetes chart-values editor moves to the new renderer.
• Theme-token normalization of the renderer so it follows light/dark.

Verification

• Frontend unit suites green; production build clean.
• Live-verified against a fixture OSB broker with a schema-bearing plan: nested object / enum / number / boolean widgets render; Form↔JSON round-trips both directions; numbers emit as numbers; a type mismatch warns without blocking; dark mode is correct.

Follow-ups (separate)

• Surface service-plan parameter-schema status (badge + read-only preview) on marketplace plan cards #5493 — surface a parameter-schema status badge + read-only preview on marketplace plan cards.
• Normalize remaining hard-coded / light-only colors to semantic theme tokens (light/dark) #5494 — normalize remaining hard-coded / light-only colors to semantic theme tokens.

[norman-abramovitz]

LGTM maybe some cleanup on text styling but does not hold up getting the functionality back.