fix: generate web panel certs per build and clean up mqtt env flags

arch/esp32/extra_scripts/generate_web_panel_cert.py

@@ -0,0 +1,77 @@
+Import("env")
+
+from pathlib import Path
+import subprocess
+import tempfile
+
+
+def render_pem_array(name, pem_text):
+    lines = []
+    for chunk in pem_text.splitlines(keepends=True):
+        escaped = chunk.replace("\\", "\\\\").replace('"', '\\"').replace("\n", "\\n")
+        lines.append(f'    "{escaped}"')
+    joined = "\n".join(lines) if lines else '    ""'
+    return f"static const char {name}[] =\n{joined};\n"
+
+
+project_dir = Path(env["PROJECT_DIR"])
+header_path = project_dir / "src/helpers/mqtt/WebPanelCert.h"
+
+if header_path.exists():
+    existing = header_path.read_text()
+    if "AUTO-GENERATED BY generate_web_panel_cert.py" in existing and "kServerKeyPem" in existing:
+        Return()
+
+with tempfile.TemporaryDirectory() as tmp:
+    tmp_path = Path(tmp)
+    key_path = tmp_path / "web-panel-key.pem"
+    cert_path = tmp_path / "web-panel-cert.pem"
+
+    try:
+        subprocess.run(
+            ["openssl", "ecparam", "-name", "prime256v1", "-genkey", "-noout", "-out", str(key_path)],
+            check=True,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            text=True,
+        )
+        subprocess.run(
+            [
+                "openssl",
+                "req",
+                "-new",
+                "-x509",
+                "-key",
+                str(key_path),
+                "-out",
+                str(cert_path),
+                "-days",
+                "3650",
+                "-subj",
+                "/CN=meshcore-local",
+            ],
+            check=True,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            text=True,
+        )
+    except FileNotFoundError as exc:
+        raise RuntimeError("openssl is required to generate the web panel certificate header") from exc
+    except subprocess.CalledProcessError as exc:
+        raise RuntimeError(
+            f"openssl failed while generating the web panel certificate header: {exc.stderr.strip()}"
+        ) from exc
+
+    cert_pem = cert_path.read_text()
+    key_pem = key_path.read_text()
+
+header_path.parent.mkdir(parents=True, exist_ok=True)
+header_path.write_text(
+    "#pragma once\n\n"
+    "// AUTO-GENERATED BY generate_web_panel_cert.py. DO NOT COMMIT.\n\n"
+    "namespace mqtt_web_panel_cert {\n\n"
+    f"{render_pem_array('kServerCertPem', cert_pem)}\n"
+    f"{render_pem_array('kServerKeyPem', key_pem)}"
+    "}\n",
+    encoding="utf-8",
+)