PatchDL 0.0.1: scan, resolve, download and install PS5 game patches

Standalone PS5 payload with an embedded web UI on :12880, no etaHEN.

- Scans installed titles and classifies the source (genuine install,
  ShadowMountPlus mount, preinstall, unknown) from the on-disk layout.
- Reads name, installed version and the Sony version.xml URL from the PS5
  app database (vendored SQLite).
- Resolves version.xml past nanoDNS via a raw DNS query, TLS pinned to the
  SCEI DNAS root.
- Filters patches to the newest one compatible with the current firmware.
- Downloads the patch and installs it through AppInstUtil (sysmodule loaded
  at runtime), gated to genuine installs with a package title-id match guard.
- Action-based UI filters and an on-screen startup notification with the URL.

src/patchdl_net.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <stddef.h>
+
+typedef struct {
+    char  *data;
+    size_t size;
+    size_t cap;
+} patchdl_buf_t;
+
+patchdl_buf_t *patchdl_buf_new(void);
+void           patchdl_buf_free(patchdl_buf_t *b);
+
+int patchdl_http_get(const char *url, patchdl_buf_t *out);
+
+/* Stream a URL to a file on disk (for large PKG downloads). Returns 0 on
+   success and writes the byte count to *bytes_out. */
+int patchdl_http_download(const char *url, const char *dest_path,
+                          long long *bytes_out);
+
+/* Diagnostic: run the GET pipeline for `url` and write a JSON report
+   (dns result/ip, curl code, http status, bytes) into `out_json`. */
+void patchdl_net_diag(const char *url, char *out_json, size_t sz);