Neon / portal template support (#713)

TODOs:
- [x] Do restart when checkout / restore if there is a DB
- [x] List all branches (branch id, name, date)
- [x] Allow checking out versions with no DB
- [x] safeguard to never delete main branches
- [x] create app hook for neon template
- [x] weird UX with connector on configure panel
- [x] tiny neon logo in connector
- [x] deploy to vercel
- [x] build forgot password page
- [x] what about email setup
- [x] lots of imgix errors
- [x] edit file - db snapshot
- [x] DYAD_DISABLE_DB_PUSH
- [ ] update portal doc
- [x] switch preview branch to be read-only endpoint
- [x] disable supabase sys prompt if neon is enabled
- [ ] https://payloadcms.com/docs/upload/storage-adapters
- [x] need to use main branch...

Phase 2?
- [x] generate DB migrations

src/ipc/utils/app_env_var_utils.ts

@@ -3,7 +3,109 @@
  * Environment variables are sensitive and should not be logged.
  */
 
+import { getDyadAppPath } from "@/paths/paths";
 import { EnvVar } from "../ipc_types";
+import path from "path";
+import fs from "fs";
+import log from "electron-log";
+
+const logger = log.scope("app_env_var_utils");
+
+export const ENV_FILE_NAME = ".env.local";
+
+function getEnvFilePath({ appPath }: { appPath: string }): string {
+  return path.join(getDyadAppPath(appPath), ENV_FILE_NAME);
+}
+
+export async function updatePostgresUrlEnvVar({
+  appPath,
+  connectionUri,
+}: {
+  appPath: string;
+  connectionUri: string;
+}) {
+  // Given the connection uri, update the env var for POSTGRES_URL
+  const envVars = parseEnvFile(await readEnvFile({ appPath }));
+
+  // Find existing POSTGRES_URL or add it if it doesn't exist
+  const existingVar = envVars.find((envVar) => envVar.key === "POSTGRES_URL");
+  if (existingVar) {
+    existingVar.value = connectionUri;
+  } else {
+    envVars.push({
+      key: "POSTGRES_URL",
+      value: connectionUri,
+    });
+  }
+
+  const envFileContents = serializeEnvFile(envVars);
+  await fs.promises.writeFile(getEnvFilePath({ appPath }), envFileContents);
+}
+
+export async function updateDbPushEnvVar({
+  appPath,
+  disabled,
+}: {
+  appPath: string;
+  disabled: boolean;
+}) {
+  try {
+    // Try to read existing env file
+    let envVars: EnvVar[];
+    try {
+      const content = await readEnvFile({ appPath });
+      envVars = parseEnvFile(content);
+    } catch {
+      // If file doesn't exist, start with empty array
+      envVars = [];
+    }
+
+    // Update or add DYAD_DISABLE_DB_PUSH
+    const existingVar = envVars.find(
+      (envVar) => envVar.key === "DYAD_DISABLE_DB_PUSH",
+    );
+    if (existingVar) {
+      existingVar.value = disabled ? "true" : "false";
+    } else {
+      envVars.push({
+        key: "DYAD_DISABLE_DB_PUSH",
+        value: disabled ? "true" : "false",
+      });
+    }
+
+    const envFileContents = serializeEnvFile(envVars);
+    await fs.promises.writeFile(getEnvFilePath({ appPath }), envFileContents);
+  } catch (error) {
+    logger.error(
+      `Failed to update DB push environment variable for app ${appPath}: ${error}`,
+    );
+    throw error;
+  }
+}
+
+export async function readPostgresUrlFromEnvFile({
+  appPath,
+}: {
+  appPath: string;
+}): Promise<string> {
+  const contents = await readEnvFile({ appPath });
+  const envVars = parseEnvFile(contents);
+  const postgresUrl = envVars.find(
+    (envVar) => envVar.key === "POSTGRES_URL",
+  )?.value;
+  if (!postgresUrl) {
+    throw new Error("POSTGRES_URL not found in .env.local");
+  }
+  return postgresUrl;
+}
+
+export async function readEnvFile({
+  appPath,
+}: {
+  appPath: string;
+}): Promise<string> {
+  return fs.promises.readFile(getEnvFilePath({ appPath }), "utf8");
+}
 
 // Helper function to parse .env.local file content
 export function parseEnvFile(content: string): EnvVar[] {