💥(backend) remove the documents/{id}/content/ endpoint

Both its PATCH and its GET: the content of a document is saved and
served by the collaboration server. The `content_patch` and
`content_retrieve` abilities go with it.

src/backend/core/api/utils.py

@@ -1,6 +1,5 @@
 """Util to generate S3 authorization headers for object storage access control"""
 
-import datetime as dt
 import time
 from abc import ABC, abstractmethod
 
@@ -197,36 +196,3 @@ class AIUserRateThrottle(AIBaseRateThrottle):
             if x_forwarded_for
             else request.META.get("REMOTE_ADDR")
         )
-
-
-def get_content_metadata_cache_key(document_id):
-    """Return the cache key used to store content metadata."""
-    return f"docs:content-metadata:{document_id!s}"
-
-
-def parse_http_conditional_headers(request):
-    """Extract and normalize `If-None-Match` and `If-Modified-Since`.
-
-    The `W/` weak prefix is stripped from the ETag because reverse proxies
-    (e.g. nginx with gzip) rewrite strong ETags into weak ones, which would
-    otherwise break a strict equality check in production.
-    """
-    if_none_match = request.META.get("HTTP_IF_NONE_MATCH")
-    if if_none_match and if_none_match.startswith("W/"):
-        if_none_match = if_none_match.removeprefix("W/")
-
-    if_modified_since_dt = None
-    if not (if_modified_since := request.META.get("HTTP_IF_MODIFIED_SINCE")):
-        return if_none_match, if_modified_since_dt
-
-    try:
-        if_modified_since_dt = dt.datetime.strptime(
-            if_modified_since, "%a, %d %b %Y %H:%M:%S %Z"
-        )
-    except ValueError:
-        if_modified_since_dt = None
-    else:
-        if not if_modified_since_dt.tzinfo:
-            if_modified_since_dt = if_modified_since_dt.replace(tzinfo=dt.timezone.utc)
-
-    return if_none_match, if_modified_since_dt