feat(tools): implement CRUD operations for thoughts and projects

* Add tools for creating, retrieving, updating, and deleting thoughts.
* Implement project management tools for creating and listing projects.
* Introduce linking functionality between thoughts.
* Add search and recall capabilities for thoughts based on semantic queries.
* Implement statistics and summarization tools for thought analysis.
* Create database migrations for thoughts, projects, and links.
* Add helper functions for UUID parsing and project resolution.

internal/tools/helpers.go

@@ -0,0 +1,87 @@
+package tools
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/google/uuid"
+	"github.com/jackc/pgx/v5"
+	"github.com/modelcontextprotocol/go-sdk/mcp"
+
+	"git.warky.dev/wdevs/amcs/internal/session"
+	"git.warky.dev/wdevs/amcs/internal/store"
+	thoughttypes "git.warky.dev/wdevs/amcs/internal/types"
+)
+
+func parseUUID(id string) (uuid.UUID, error) {
+	parsed, err := uuid.Parse(strings.TrimSpace(id))
+	if err != nil {
+		return uuid.Nil, fmt.Errorf("invalid id %q: %w", id, err)
+	}
+	return parsed, nil
+}
+
+func sessionID(req *mcp.CallToolRequest) (string, error) {
+	if req == nil || req.Session == nil || req.Session.ID() == "" {
+		return "", fmt.Errorf("tool requires an MCP session")
+	}
+	return req.Session.ID(), nil
+}
+
+func resolveProject(ctx context.Context, db *store.DB, sessions *session.ActiveProjects, req *mcp.CallToolRequest, raw string, required bool) (*thoughttypes.Project, error) {
+	projectRef := strings.TrimSpace(raw)
+	if projectRef == "" && sessions != nil && req != nil && req.Session != nil {
+		if activeID, ok := sessions.Get(req.Session.ID()); ok {
+			project, err := db.GetProject(ctx, activeID.String())
+			if err == nil {
+				return &project, nil
+			}
+			if err != pgx.ErrNoRows {
+				return nil, err
+			}
+		}
+	}
+
+	if projectRef == "" {
+		if required {
+			return nil, fmt.Errorf("project is required")
+		}
+		return nil, nil
+	}
+
+	project, err := db.GetProject(ctx, projectRef)
+	if err != nil {
+		if err == pgx.ErrNoRows {
+			return nil, fmt.Errorf("project %q not found", projectRef)
+		}
+		return nil, err
+	}
+
+	return &project, nil
+}
+
+func formatContextBlock(header string, lines []string) string {
+	if len(lines) == 0 {
+		return header + "\n\nNo matching thoughts."
+	}
+	return header + "\n\n" + strings.Join(lines, "\n\n")
+}
+
+func thoughtContextLine(index int, content string, metadata thoughttypes.ThoughtMetadata, similarity float64) string {
+	label := fmt.Sprintf("%d. %s", index+1, strings.TrimSpace(content))
+	parts := make([]string, 0, 3)
+	if len(metadata.Topics) > 0 {
+		parts = append(parts, "topics="+strings.Join(metadata.Topics, ", "))
+	}
+	if metadata.Type != "" {
+		parts = append(parts, "type="+metadata.Type)
+	}
+	if similarity > 0 {
+		parts = append(parts, fmt.Sprintf("similarity=%.3f", similarity))
+	}
+	if len(parts) == 0 {
+		return label
+	}
+	return label + "\n[" + strings.Join(parts, " | ") + "]"
+}