feat(ingestion): implement brain_ingest MCP tool

Wraps pipeline.Run with the existing LLM client. Mirrors the HTTP
/ingest and /ingest-path semantics — accepts either path or
content+source, validates mutual exclusion, surfaces an explicit error
when the LLM client is not configured (test-mode).

ctx is threaded through to pipeline.Run for cancellation.

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

ingestion/internal/mcp/handlers.go

@@ -4,8 +4,11 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"path/filepath"
+	"strings"
 
 	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
+	"github.com/mathiasbq/hyperguild/ingestion/internal/extract"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/pipeline"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/search"
 )
@@ -155,3 +158,58 @@ func (s *Server) brainIngestRaw(ctx context.Context, args json.RawMessage) (json
 	}
 	return json.Marshal(map[string]any{"pages": pages, "warnings": warnings})
 }
+
+type brainIngestArgs struct {
+	Content string `json:"content,omitempty"`
+	Source  string `json:"source,omitempty"`
+	Path    string `json:"path,omitempty"`
+	DryRun  bool   `json:"dry_run,omitempty"`
+}
+
+func (s *Server) brainIngest(ctx context.Context, args json.RawMessage) (json.RawMessage, error) {
+	var a brainIngestArgs
+	if err := json.Unmarshal(args, &a); err != nil {
+		return nil, fmt.Errorf("parse args: %w", err)
+	}
+	if a.Path != "" && a.Content != "" {
+		return nil, fmt.Errorf("path and content+source are mutually exclusive")
+	}
+	if a.Path == "" && a.Content == "" {
+		return nil, fmt.Errorf("either path or content+source is required")
+	}
+	if s.pipeline.Complete == nil {
+		return nil, fmt.Errorf("LLM not configured: set INGEST_LLM_URL")
+	}
+
+	if a.Path != "" {
+		text, err := extract.Text(a.Path)
+		if err != nil {
+			return nil, fmt.Errorf("extract: %w", err)
+		}
+		source := a.Source
+		if source == "" {
+			source = filepath.Base(strings.TrimSuffix(a.Path, filepath.Ext(a.Path)))
+		}
+		return s.runIngest(ctx, text, source, a.DryRun)
+	}
+	if a.Source == "" {
+		return nil, fmt.Errorf("source is required when content is provided")
+	}
+	return s.runIngest(ctx, a.Content, a.Source, a.DryRun)
+}
+
+func (s *Server) runIngest(ctx context.Context, content, source string, dryRun bool) (json.RawMessage, error) {
+	result, err := pipeline.Run(ctx, s.pipeline, s.brainDir, content, source, dryRun)
+	if err != nil {
+		return nil, fmt.Errorf("ingest: %w", err)
+	}
+	pages := result.Pages
+	if pages == nil {
+		pages = []string{}
+	}
+	warnings := result.Warnings
+	if warnings == nil {
+		warnings = []string{}
+	}
+	return json.Marshal(map[string]any{"pages": pages, "warnings": warnings})
+}