feat(07-01): implement task quality gate validation module

- validateTaskCreation: min 50 char description, heartbeat bypass, acceptance criteria check
- checkAcceptanceCriteria: 12 keyword patterns for structured task definitions
- checkCapabilityMatch: word-overlap matching with skill fallback and graceful degradation
- All 25 unit tests passing across TASK-01, TASK-02, TASK-03 requirements

src/main/task-quality-gates.ts

@@ -0,0 +1,160 @@
+/**
+ * Task Quality Gates — pure validation functions for task creation.
+ *
+ * Called by IPC handlers, API server, and automation service to enforce
+ * minimum description quality, acceptance criteria, and capability matching.
+ */
+
+// ---------------------------------------------------------------------------
+// Types
+// ---------------------------------------------------------------------------
+
+export interface TaskValidationResult {
+  valid: boolean;
+  errors: string[];
+  warnings: string[];
+}
+
+export interface CapabilityMatchResult {
+  matched: boolean;
+  warning?: string;
+}
+
+/** Minimal DB interface for capability matching — keeps the function testable with mocks. */
+export interface CapabilityMatchDb {
+  getAgent(id: string): { name: string; capabilities: string };
+  listAgentSkillAssignments(id: string): string[];
+  getCompanySkill(companyId: string, skillId: string): { name: string; description: string | null; slug: string } | null;
+}
+
+// ---------------------------------------------------------------------------
+// Constants
+// ---------------------------------------------------------------------------
+
+const MIN_DESCRIPTION_LENGTH = 50;
+
+export const ACCEPTANCE_CRITERIA_KEYWORDS: readonly string[] = [
+  "acceptance criteria",
+  "done when",
+  "success criteria",
+  "definition of done",
+  "requirements:",
+  "must:",
+  "should:",
+  "- [ ]",
+  "- [x]",
+  "deliverable:",
+  "expected outcome",
+  "exit criteria",
+];
+
+// ---------------------------------------------------------------------------
+// checkAcceptanceCriteria
+// ---------------------------------------------------------------------------
+
+export function checkAcceptanceCriteria(description: string): { hasCriteria: boolean; suggestion: string } {
+  const lower = description.toLowerCase();
+  const found = ACCEPTANCE_CRITERIA_KEYWORDS.some((kw) => lower.includes(kw));
+
+  if (found) {
+    return { hasCriteria: true, suggestion: "" };
+  }
+
+  return {
+    hasCriteria: false,
+    suggestion:
+      'Task description should include acceptance criteria. Add a "Done when:" or "Acceptance criteria:" section, or use checkbox items (- [ ]) to define success conditions.',
+  };
+}
+
+// ---------------------------------------------------------------------------
+// validateTaskCreation
+// ---------------------------------------------------------------------------
+
+export function validateTaskCreation(
+  input: { title: string; description: string },
+  isHeartbeat: boolean,
+): TaskValidationResult {
+  // Heartbeat tasks bypass all validation
+  if (isHeartbeat) {
+    return { valid: true, errors: [], warnings: [] };
+  }
+
+  const errors: string[] = [];
+  const warnings: string[] = [];
+
+  // TASK-01: Minimum description length
+  if (input.description.length < MIN_DESCRIPTION_LENGTH) {
+    errors.push(
+      `Task description must be at least ${MIN_DESCRIPTION_LENGTH} characters (currently ${input.description.length}). Add details about what needs to be done, expected behavior, and any constraints.`,
+    );
+  }
+
+  // TASK-02: Acceptance criteria detection (only check if length passes)
+  if (input.description.length >= MIN_DESCRIPTION_LENGTH) {
+    const criteria = checkAcceptanceCriteria(input.description);
+    if (!criteria.hasCriteria) {
+      errors.push(criteria.suggestion);
+    }
+  }
+
+  return { valid: errors.length === 0, errors, warnings };
+}
+
+// ---------------------------------------------------------------------------
+// checkCapabilityMatch
+// ---------------------------------------------------------------------------
+
+/** Tokenize text into words >3 chars, same pattern as database.ts autoAssignTask */
+function tokenize(text: string): string[] {
+  return text.toLowerCase().split(/\W+/).filter((w) => w.length > 3);
+}
+
+export function checkCapabilityMatch(
+  db: CapabilityMatchDb,
+  agentId: string,
+  taskDescription: string,
+  companyId: string,
+): CapabilityMatchResult {
+  const taskWords = tokenize(taskDescription);
+
+  // Nothing to match against — task description too short/vague
+  if (taskWords.length === 0) {
+    return { matched: true };
+  }
+
+  const agent = db.getAgent(agentId);
+  const capWords = tokenize(agent.capabilities);
+  const capabilityOverlap = taskWords.filter((w) => capWords.includes(w)).length;
+
+  // Check skill assignments for additional matching (graceful degradation)
+  let skillOverlap = 0;
+  try {
+    const skillIds = db.listAgentSkillAssignments(agentId);
+    for (const skillId of skillIds) {
+      const skill = db.getCompanySkill(companyId, skillId);
+      if (skill) {
+        const skillWords = tokenize(`${skill.name} ${skill.description ?? ""} ${skill.slug}`);
+        skillOverlap += taskWords.filter((w) => skillWords.includes(w)).length;
+      }
+    }
+  } catch {
+    // Skill system may not be available — graceful degradation per D-07
+  }
+
+  // Direct capability or skill overlap found
+  if (capabilityOverlap > 0 || skillOverlap > 0) {
+    return { matched: true };
+  }
+
+  // No capabilities defined at all — graceful degradation (Pitfall 4)
+  if (capWords.length === 0 && skillOverlap === 0) {
+    return { matched: true };
+  }
+
+  // Agent has capabilities but no overlap — warn
+  return {
+    matched: false,
+    warning: `Agent "${agent.name}" may lack skills for this task. Their capabilities (${agent.capabilities.slice(0, 80)}...) have no overlap with the task description. Consider reassigning.`,
+  };
+}