feat(pathways): add AI-powered 'Why Match' job analysis

- Add job_match_insights table for caching AI explanations
- Create /api/pathways/match-insights endpoint using AI SDK generateObject
- Add WhyMatch component with expandable bullet points and match score
- Integrate into SwipeDetailSheet and PathwaysJobPanel
- Results cached in DB with resume/job hash for invalidation

Author: thomasdavis

apps/registry/app/api/pathways/match-insights/route.js

@@ -0,0 +1,222 @@
+import { generateObject } from 'ai';
+import { openai } from '@ai-sdk/openai';
+import { createClient } from '@supabase/supabase-js';
+import { z } from 'zod';
+import crypto from 'crypto';
+
+function getSupabase() {
+  if (!process.env.SUPABASE_KEY) {
+    throw new Error('SUPABASE_KEY environment variable is required');
+  }
+  return createClient(
+    'https://itxuhvvwryeuzuyihpkp.supabase.co',
+    process.env.SUPABASE_KEY
+  );
+}
+
+// Create a hash of content for cache invalidation
+function hashContent(content) {
+  return crypto
+    .createHash('md5')
+    .update(JSON.stringify(content))
+    .digest('hex')
+    .slice(0, 16);
+}
+
+const insightsSchema = z.object({
+  bullets: z.array(
+    z.object({
+      emoji: z.string().describe('A relevant emoji for this point'),
+      title: z.string().describe('Short bold title (2-4 words)'),
+      description: z.string().describe('Brief explanation (1-2 sentences)'),
+    })
+  ),
+  matchScore: z
+    .number()
+    .min(0)
+    .max(100)
+    .describe('Overall match percentage based on skills and experience'),
+  summary: z
+    .string()
+    .describe('One sentence summary of why this could be a good fit'),
+});
+
+const SYSTEM_PROMPT = `You are a career advisor helping a job seeker understand why they might be a good fit for a specific role.
+
+Analyze the resume and job posting, then provide:
+1. 4-6 specific bullet points explaining why this person could be a strong candidate
+2. Focus on concrete skill matches, relevant experience, and potential growth areas
+3. Be honest but encouraging - mention any gaps constructively
+4. Each bullet should have a relevant emoji, a short title, and a brief description
+
+Consider:
+- Direct skill matches between resume and job requirements
+- Relevant experience and projects
+- Transferable skills
+- Company culture fit indicators
+- Growth opportunities this role offers`;
+
+export async function POST(request) {
+  const supabase = getSupabase();
+
+  try {
+    const { userId, jobId, resume, job } = await request.json();
+
+    if (!userId || !jobId || !resume || !job) {
+      return Response.json(
+        { error: 'userId, jobId, resume, and job are required' },
+        { status: 400 }
+      );
+    }
+
+    const resumeHash = hashContent(resume);
+    const jobHash = hashContent(job);
+
+    // Check cache first
+    const { data: cached } = await supabase
+      .from('job_match_insights')
+      .select('*')
+      .eq('user_id', userId)
+      .eq('job_id', jobId)
+      .single();
+
+    // Return cached if hashes match (content hasn't changed)
+    if (
+      cached &&
+      cached.resume_hash === resumeHash &&
+      cached.job_hash === jobHash
+    ) {
+      return Response.json({
+        ...cached.insights,
+        cached: true,
+        generatedAt: cached.created_at,
+      });
+    }
+
+    // Generate new insights
+    const { object, usage } = await generateObject({
+      model: openai('gpt-4.1'),
+      schema: insightsSchema,
+      system: SYSTEM_PROMPT,
+      prompt: `
+RESUME:
+${JSON.stringify(resume, null, 2)}
+
+JOB POSTING:
+Title: ${job.title}
+Company: ${job.company}
+${job.description ? `Description: ${job.description}` : ''}
+${
+  job.skills?.length
+    ? `Required Skills: ${job.skills
+        .map((s) => (typeof s === 'string' ? s : s.name))
+        .join(', ')}`
+    : ''
+}
+${
+  job.bonusSkills?.length
+    ? `Bonus Skills: ${job.bonusSkills
+        .map((s) => (typeof s === 'string' ? s : s.name))
+        .join(', ')}`
+    : ''
+}
+${
+  job.location
+    ? `Location: ${
+        typeof job.location === 'string'
+          ? job.location
+          : `${job.location.city || ''}, ${job.location.region || ''}`
+      }`
+    : ''
+}
+${job.remote ? 'Remote: Yes' : ''}
+${
+  job.salaryMin && job.salaryMax
+    ? `Salary Range: $${job.salaryMin.toLocaleString()} - $${job.salaryMax.toLocaleString()}`
+    : ''
+}
+
+Provide specific, actionable insights about why this person could be a good fit for this role.`,
+    });
+
+    // Upsert to cache
+    const { error: upsertError } = await supabase
+      .from('job_match_insights')
+      .upsert(
+        {
+          user_id: userId,
+          job_id: jobId,
+          insights: object,
+          resume_hash: resumeHash,
+          job_hash: jobHash,
+          model: 'gpt-4.1',
+          tokens_used: usage?.totalTokens || null,
+          updated_at: new Date().toISOString(),
+        },
+        { onConflict: 'user_id,job_id' }
+      );
+
+    if (upsertError) {
+      console.error('Error caching insights:', upsertError);
+      // Don't fail the request, just log the error
+    }
+
+    return Response.json({
+      ...object,
+      cached: false,
+      generatedAt: new Date().toISOString(),
+    });
+  } catch (error) {
+    console.error('Error generating match insights:', error);
+    return Response.json(
+      { error: error.message || 'Failed to generate insights' },
+      { status: 500 }
+    );
+  }
+}
+
+export async function GET(request) {
+  const supabase = getSupabase();
+
+  try {
+    const { searchParams } = new URL(request.url);
+    const userId = searchParams.get('userId');
+    const jobId = searchParams.get('jobId');
+
+    if (!userId || !jobId) {
+      return Response.json(
+        { error: 'userId and jobId are required' },
+        { status: 400 }
+      );
+    }
+
+    const { data, error } = await supabase
+      .from('job_match_insights')
+      .select('*')
+      .eq('user_id', userId)
+      .eq('job_id', jobId)
+      .single();
+
+    if (error && error.code !== 'PGRST116') {
+      // PGRST116 = no rows returned
+      console.error('Error fetching insights:', error);
+      return Response.json(
+        { error: 'Failed to fetch insights' },
+        { status: 500 }
+      );
+    }
+
+    if (!data) {
+      return Response.json({ exists: false });
+    }
+
+    return Response.json({
+      ...data.insights,
+      cached: true,
+      generatedAt: data.created_at,
+    });
+  } catch (error) {
+    console.error('Error in insights GET:', error);
+    return Response.json({ error: 'Internal server error' }, { status: 500 });
+  }
+}