feat: Production readiness improvements for WHOOSH council formation

Major security, observability, and configuration improvements:

## Security Hardening
- Implemented configurable CORS (no more wildcards)
- Added comprehensive auth middleware for admin endpoints
- Enhanced webhook HMAC validation
- Added input validation and rate limiting
- Security headers and CSP policies

## Configuration Management
- Made N8N webhook URL configurable (WHOOSH_N8N_BASE_URL)
- Replaced all hardcoded endpoints with environment variables
- Added feature flags for LLM vs heuristic composition
- Gitea fetch hardening with EAGER_FILTER and FULL_RESCAN options

## API Completeness
- Implemented GetCouncilComposition function
- Added GET /api/v1/councils/{id} endpoint
- Council artifacts API (POST/GET /api/v1/councils/{id}/artifacts)
- /admin/health/details endpoint with component status
- Database lookup for repository URLs (no hardcoded fallbacks)

## Observability & Performance
- Added OpenTelemetry distributed tracing with goal/pulse correlation
- Performance optimization database indexes
- Comprehensive health monitoring
- Enhanced logging and error handling

## Infrastructure
- Production-ready P2P discovery (replaces mock implementation)
- Removed unused Redis configuration
- Enhanced Docker Swarm integration
- Added migration files for performance indexes

## Code Quality
- Comprehensive input validation
- Graceful error handling and failsafe fallbacks
- Backwards compatibility maintained
- Following security best practices

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

vendor/go.opentelemetry.io/otel/trace/embedded/embedded.go

@@ -0,0 +1,56 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package embedded provides interfaces embedded within the [OpenTelemetry
+// trace API].
+//
+// Implementers of the [OpenTelemetry trace API] can embed the relevant type
+// from this package into their implementation directly. Doing so will result
+// in a compilation error for users when the [OpenTelemetry trace API] is
+// extended (which is something that can happen without a major version bump of
+// the API package).
+//
+// [OpenTelemetry trace API]: https://pkg.go.dev/go.opentelemetry.io/otel/trace
+package embedded // import "go.opentelemetry.io/otel/trace/embedded"
+
+// TracerProvider is embedded in
+// [go.opentelemetry.io/otel/trace.TracerProvider].
+//
+// Embed this interface in your implementation of the
+// [go.opentelemetry.io/otel/trace.TracerProvider] if you want users to
+// experience a compilation error, signaling they need to update to your latest
+// implementation, when the [go.opentelemetry.io/otel/trace.TracerProvider]
+// interface is extended (which is something that can happen without a major
+// version bump of the API package).
+type TracerProvider interface{ tracerProvider() }
+
+// Tracer is embedded in [go.opentelemetry.io/otel/trace.Tracer].
+//
+// Embed this interface in your implementation of the
+// [go.opentelemetry.io/otel/trace.Tracer] if you want users to experience a
+// compilation error, signaling they need to update to your latest
+// implementation, when the [go.opentelemetry.io/otel/trace.Tracer] interface
+// is extended (which is something that can happen without a major version bump
+// of the API package).
+type Tracer interface{ tracer() }
+
+// Span is embedded in [go.opentelemetry.io/otel/trace.Span].
+//
+// Embed this interface in your implementation of the
+// [go.opentelemetry.io/otel/trace.Span] if you want users to experience a
+// compilation error, signaling they need to update to your latest
+// implementation, when the [go.opentelemetry.io/otel/trace.Span] interface is
+// extended (which is something that can happen without a major version bump of
+// the API package).
+type Span interface{ span() }