feat(mail): support gzip compressed email storage via ENABLE_MAIL_GZIP (#933)

* feat(mail): support gzip compressed email storage in D1 raw_blob column

Add ENABLE_MAIL_GZIP env var to optionally gzip-compress incoming emails
into a new raw_blob BLOB column, saving D1 storage space. Reading is
backward-compatible: prioritizes raw_blob (decompress) with fallback to
plaintext raw field. Includes DB migration v0.0.7, docs, and changelogs.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: gzip fallback on missing column + decouple resolve from handleListQuery

- email/index.ts: gzip INSERT failure now falls back to plaintext INSERT
  instead of silently losing the email (P1: data loss prevention)
- common.ts: add handleMailListQuery for raw_mails-specific list queries
  with resolveRawEmailList, keeping handleListQuery generic
- Replace handleListQuery → handleMailListQuery in mails_api, admin_mail_api,
  user_mail_api (only raw_mails callers)
- Add e2e test infrastructure: worker-gzip service, wrangler.toml.e2e.gzip,
  api-gzip playwright project, mail-gzip.spec.ts with 4 test cases

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: address CodeRabbit review feedback for gzip feature

- Use destructuring in resolveRawEmailRow to truly remove raw_blob key
- Narrow fallback scope: only fallback to plaintext on compression failure
  or missing raw_blob column, re-throw other DB errors
- Clean unused imports in e2e gzip test

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: add try-catch in resolveRawEmail to prevent single corrupt blob from failing entire list

A corrupted raw_blob would cause decompressBlob to throw, which with
Promise.all in resolveRawEmailList would reject the entire batch query.
Now catches decompression errors and falls back to row.raw field.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix(mail): align sendAdminInternalMail with gzip storage path

sendAdminInternalMail now respects ENABLE_MAIL_GZIP: compresses to
raw_blob when enabled, with fallback to plaintext on failure.
Added e2e test verifying admin internal mail is readable under gzip.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix(e2e): match admin internal mail by body content instead of encoded subject

mimetext base64-encodes the Subject header, so the raw MIME string
does not contain the literal subject text. Match on body content
(balance: 99) which is plaintext.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix(e2e): add WORKER_GZIP_URL guard and length assertions in gzip tests

Address CodeRabbit feedback:
- Skip gzip tests when WORKER_GZIP_URL is not set to prevent false positives
- Assert results array length before accessing [0] for clearer error messages

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix(mail): narrow gzip fallback scope and fix webhook query compatibility

- sendAdminInternalMail: separate compress vs DB error handling, only
  fallback to plaintext on compression failure or missing raw_blob
  column, rethrow other DB errors (aligns with email/index.ts)
- Webhook test endpoints: use SELECT * instead of explicit raw_blob
  column reference, so pre-migration databases don't 500
- Docs/changelog: clarify that db_migration must run before enabling
  ENABLE_MAIL_GZIP

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix(telegram): use generic Record type for raw_mails query result

Align with other query sites — avoid hardcoding raw_blob in the
TypeScript type annotation so the query works with or without the
column after migration.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* refactor(models): add RawMailRow type and unify raw_mails query typing

Add RawMailRow type to models with raw_blob as optional field, replacing
ad-hoc Record<string, unknown> and inline type annotations across
webhook test endpoints, telegram API, and gzip utilities.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

e2e/docker-compose.yml

@@ -41,10 +41,28 @@ services:
       context: ..
       dockerfile: e2e/Dockerfile.worker
     ports:
-      - "8788:8788"
-    command: ["pnpm", "exec", "wrangler", "dev", "--port", "8788", "--ip", "0.0.0.0"]
+      - "8790:8790"
+    command: ["pnpm", "exec", "wrangler", "dev", "--port", "8790", "--ip", "0.0.0.0"]
     volumes:
       - ./fixtures/wrangler.toml.e2e.env-off:/app/worker/wrangler.toml:ro
+    depends_on:
+      - mailpit
+    healthcheck:
+      test: ["CMD", "curl", "-sf", "http://localhost:8790/health_check"]
+      interval: 3s
+      timeout: 5s
+      start_period: 10s
+      retries: 20
+
+  worker-gzip:
+    build:
+      context: ..
+      dockerfile: e2e/Dockerfile.worker
+      args:
+        WRANGLER_TOML: e2e/fixtures/wrangler.toml.e2e.gzip
+    ports:
+      - "8788:8788"
+    command: ["pnpm", "exec", "wrangler", "dev", "--port", "8788", "--ip", "0.0.0.0"]
     depends_on:
       - mailpit
     healthcheck:
@@ -108,7 +126,8 @@ services:
     environment:
       WORKER_URL: http://worker:8787
       WORKER_URL_SUBDOMAIN: http://worker-subdomain:8789
-      WORKER_URL_ENV_OFF: http://worker-env-off:8788
+      WORKER_URL_ENV_OFF: http://worker-env-off:8790
+      WORKER_GZIP_URL: http://worker-gzip:8788
       FRONTEND_URL: https://frontend:5173
       MAILPIT_API: http://mailpit:8025/api
       SMTP_PROXY_HOST: smtp-proxy
@@ -125,6 +144,8 @@ services:
         condition: service_healthy
       worker-env-off:
         condition: service_healthy
+      worker-gzip:
+        condition: service_healthy
       frontend:
         condition: service_started
       smtp-proxy: