add structured logging for admin/partage form submissions + migration system

- AppLogger: JSON-line logger in storage/logs/form-submissions.log
- Logs submissions (admin + partage) with IP, UA, thesis ID, author
- Logs errors with context (post keys, share slug)
- Migration runner (app/migrations/run.php) handles schema drift
- 001_add_objet_column.sql fixes production DB missing 'objet' column
- ThesisCreateController::getIdentifier() helper for logging

app/migrations/applied/001_add_objet_column.sql

@@ -0,0 +1,7 @@
+-- Add 'objet' column to theses table if it doesn't already exist.
+-- Required: the admin form sends 'objet' in POST since commit ~Apr 2024
+-- but older production databases may lack the column.
+-- SQLite 3.35+ supports ALTER TABLE ADD COLUMN (bundled with PHP 8+).
+
+ALTER TABLE theses ADD COLUMN objet TEXT NOT NULL DEFAULT 'tfe'
+    CHECK (objet IN ('tfe', 'thèse', 'frart'));

app/migrations/run.php

@@ -0,0 +1,84 @@
+#!/usr/bin/env php
+<?php
+/**
+ * Run pending migrations on the production database.
+ *
+ * Usage: php app/migrations/run.php [DB_PATH]
+ *
+ * If no DB_PATH is given, defaults to storage/posterg.db.
+ *
+ * Each migration in migrations/pending/ is applied in alphabetical order.
+ * After success, the file is moved to migrations/applied/.
+ */
+
+$root = dirname(__DIR__);
+$dbPath = $argv[1] ?? ($root . '/storage/posterg.db');
+
+if (!file_exists($dbPath)) {
+    die("Database not found: $dbPath\n");
+}
+
+$pdo = new PDO('sqlite:' . $dbPath);
+$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+// Create migrations tracking table
+$pdo->exec("
+    CREATE TABLE IF NOT EXISTS _migrations (
+        name TEXT PRIMARY KEY,
+        applied_at DATETIME DEFAULT CURRENT_TIMESTAMP
+    )
+");
+
+$applied = $pdo->query("SELECT name FROM _migrations")->fetchAll(PDO::FETCH_COLUMN);
+
+$pendingDir = $root . '/migrations/pending';
+$appliedDir = $root . '/migrations/applied';
+
+if (!is_dir($pendingDir)) {
+    echo "No pending migrations directory.\n";
+    exit(0);
+}
+
+if (!is_dir($appliedDir)) {
+    mkdir($appliedDir, 0755, true);
+}
+
+$files = glob($pendingDir . '/*.sql');
+sort($files);
+
+if (empty($files)) {
+    echo "No pending migration files.\n";
+    exit(0);
+}
+
+$count = 0;
+foreach ($files as $file) {
+    $name = basename($file);
+
+    if (in_array($name, $applied, true)) {
+        echo "Skip (already applied): $name\n";
+        continue;
+    }
+
+    echo "Applying: $name\n";
+    $sql = file_get_contents($file);
+
+    try {
+        $pdo->exec($sql);
+        $pdo->prepare("INSERT INTO _migrations (name) VALUES (?)")->execute([$name]);
+        rename($file, $appliedDir . '/' . $name);
+        $count++;
+    } catch (PDOException $e) {
+        $msg = $e->getMessage();
+        // SQLite: skip if column already exists
+        if (stripos($msg, 'duplicate column name') !== false) {
+            echo "  Already exists (skipping): $name\n";
+            $pdo->prepare("INSERT OR REPLACE INTO _migrations (name) VALUES (?)")->execute([$name]);
+            rename($file, $appliedDir . '/' . $name);
+            continue;
+        }
+        throw $e;
+    }
+}
+
+echo "$count migration(s) applied.\n";