Upgrade PHPStan to 2.x and raise analysis level from 6 to 10

- Bump phpstan/phpstan ^2.0 and szepeviktor/phpstan-wordpress ^2.0
- Move the analysis level into phpstan.neon (single source) and raise it to 10
- Add Val, a runtime coercion helper that narrows untyped WordPress boundary
  values (wpdb rows, REST params, superglobals, options) with explicit checks
  instead of blind casts, plus unit tests
- Type value-object fromRow() params as stdClass (what wpdb returns) and map
  columns through Val so unexpected shapes degrade safely
- Use %i identifier placeholders for table names in all wpdb::prepare() calls
  so every query string is a literal and identifiers are escaped by WordPress;
  raises the minimum WordPress version to 6.2 where %i was introduced
- Guard wpdb::prepare() null result before wpdb::query() in updateTax()
- Fix nullable get_permalink()/strtotime() handling, list types at REST and
  capability call sites, dead null-coalescing on checked superglobals, and
  narrow get_users() results before mapping
- Register Val method names with the ValidatedSanitizedInput sniff so it
  validates the real sanitizer around each superglobal read
- Update repository unit tests for the %i placeholder arguments

Co-Authored-By: Claude Fable 5 <[email protected]>

src/Val.php

@@ -0,0 +1,60 @@
+<?php
+declare(strict_types=1);
+
+namespace Unsupervised\Schedular;
+
+/**
+ * Runtime coercion helpers for values crossing untyped WordPress boundaries
+ * (wpdb rows, REST request params, superglobals). Each method narrows a mixed
+ * value with an explicit runtime check instead of a blind cast, so an
+ * unexpected shape degrades to a safe default rather than leaking garbage
+ * into typed code.
+ */
+final class Val {
+
+	/**
+	 * Coerce to int; non-numeric values become 0.
+	 */
+	public static function int( mixed $value ): int {
+		return is_numeric( $value ) ? (int) $value : 0;
+	}
+
+	/**
+	 * Coerce to int, preserving null (e.g. nullable DB columns).
+	 */
+	public static function intOrNull( mixed $value ): ?int {
+		return null === $value ? null : self::int( $value );
+	}
+
+	/**
+	 * Coerce to float; non-numeric values become 0.0.
+	 */
+	public static function float( mixed $value ): float {
+		return is_numeric( $value ) ? (float) $value : 0.0;
+	}
+
+	/**
+	 * Coerce to string; non-scalar values become ''.
+	 */
+	public static function string( mixed $value ): string {
+		if ( is_string( $value ) ) {
+			return $value;
+		}
+
+		return is_scalar( $value ) ? (string) $value : '';
+	}
+
+	/**
+	 * Coerce to string, preserving null (e.g. nullable DB columns).
+	 */
+	public static function stringOrNull( mixed $value ): ?string {
+		return null === $value ? null : self::string( $value );
+	}
+
+	/**
+	 * Coerce to bool using PHP truthiness (DB tinyint flags, option values).
+	 */
+	public static function bool( mixed $value ): bool {
+		return (bool) $value;
+	}
+}