Bump version from 2026.9.6 to 2026.9.16

Fix null etag crash and unify UA for article fetch with WAF retry

- Omit If-None-Match when etag is empty/NULL: httpx rejects a None
  header value before the request is even sent, and Feed.etag is
  nullable in the DB
- Fetch full article content with get_fetch_user_agent() so
  RSS_FETCH_USER_AGENT applies, retrying once with the fallback UA on
  failure (mirrors the feed fetch 403 fallback)
- Bump version to 2026.9.6

Fix 72 dependency vulnerabilities flagged by GitHub

Upgrade locked dependencies to patched versions:
- cryptography 46.0.7 -> 50.0.1
- django 6.0.4 -> 6.1.1
- idna 3.11 -> 3.19
- lxml 6.0.3 -> 6.1.3
- mistune 3.2.0 -> 3.3.4
- nltk 3.9.4 -> 3.10.3
- pillow 12.2.0 -> 12.3.0
- soupsieve 2.8.3 -> 2.9.2
- sqlparse 0.5.5 -> 0.6.0
- urllib3 2.6.3 -> 2.7.0

Note: one nltk advisory (<= 3.10.3, high) has no patched release
yet; 3.10.3 is the latest available version.

Make OpenAI retries configurable and document timeout settings

Bump version from 2026.2.21 to 2026.3.25

Bump version from 2026.2.21 to 2026.3.25

update version to 2026.2.21

Bump version from 2025.12.13 to 2026.1.7

upgrade to 2025.12.13