Curation v2 step 2: Claude Opus 5 editor, the Brief, per-provider budgets

- AnthropicBackend (Messages API, cached system block, output_config.effort,
  server-side fallbacks, refusal surfaced as an error); Llms { bulk, editor }
  with editor_or_bulk(); PriceTable-based UsageMeter per provider.
- [anthropic], [editorial], deepseek.max_concurrent_requests and
  curation.max_article_count config; startup logs resolved providers.
- Budget day is the UTC date of started_at, preloaded from
  runs.provider_costs_json; finish_run writes provider_costs_json and
  config_json. Stage A batches run concurrently with per-batch budget checks.
- Editor prompt with one-line "why" per pick; no minimum lineup size;
  --max-articles is a ceiling; top-up branch deleted; why stored on picks and
  issue_articles.why and rendered in chapters and In this issue.
- Summaries on the editor client (3k-token input, concurrency 4, bulk then
  excerpt fallback); "The Brief" replaces From the Editor; section intros gone.
- Colophon carries per-provider costs and models.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01A1rCLQeKBgnBo3oTgHuTMe

config.example.toml

@@ -4,6 +4,7 @@
 # Nested keys use a double underscore in env vars, e.g.
 #   DAILY_EPUB_MINIFLUX__API_KEY=...
 #   DAILY_EPUB_DEEPSEEK__API_KEY=...
+#   DAILY_EPUB_ANTHROPIC__API_KEY=...
 #   DAILY_EPUB_SERVER__HMAC_SECRET=...
 #   DAILY_EPUB_LOOKBACK_HOURS=30
 
@@ -13,7 +14,7 @@ target_article_count = 20
 prefilter_keep = 120
 retention_days = 21                  # EPUBs, by age
 xtc_retention_count = 5              # XTC issues, by count (~80-100 MB each)
-max_daily_usd = 2.0
+max_daily_usd = 2.0                  # DeepSeek ceiling per UTC day; [anthropic] has its own
 world_briefing = true
 
 # SQLite database file. Parent directories are created on demand.
@@ -36,14 +37,34 @@ base_url = "https://api.deepseek.com/v1"
 model = "deepseek-v4-flash"          # DeepSeek-V4-Flash-0731 (confirmed 2026-08-15)
 # api_key via DAILY_EPUB_DEEPSEEK__API_KEY env
 score_batch_size = 12
+max_concurrent_requests = 4          # stage-A batches in flight at once
 score_temperature = 0.3
-editorial_temperature = 0.8
+editorial_temperature = 0.8          # used only when DeepSeek is the fallback editor
 # USD per 1M tokens, used for the cost guardrail.
 price_input_per_mtok = 0.14
 price_cached_input_per_mtok = 0.0028
 price_output_per_mtok = 0.28
 
+# Claude is the editor: selection, summaries, The Brief and the weekly profile
+# rebuild. Every call degrades to DeepSeek when the key is missing, the daily
+# ceiling is hit, or the API refuses/fails. Server-side refusal fallback
+# (`fallbacks = "default"`) is always on. Set a spend limit in the Anthropic
+# dashboard too: `max_daily_usd` is a runaway guard, not accounting.
+[anthropic]
+enabled = true
+base_url = "https://api.anthropic.com"
+model = "claude-opus-5"
+# api_key via DAILY_EPUB_ANTHROPIC__API_KEY env
+effort = "high"                      # low | medium | high | xhigh | max
+price_input_per_mtok = 5.0
+price_cache_write_per_mtok = 6.25
+price_cache_read_per_mtok = 0.5
+price_output_per_mtok = 25.0
+max_daily_usd = 3.0
+max_concurrent_requests = 4
+
 [curation]
+max_article_count = 28               # hard ceiling; there is no minimum (§13)
 always_include_feeds = []            # miniflux feed ids or site urls
 blocked_domains = []
 # Extra paywalled hosts, merged with the built-in list (nytimes, wsj, ft, …).
@@ -66,6 +87,10 @@ good_value = 0.35
 not_for_me_value = -1.0
 verdicts_in_prompt = 60
 
+[editorial]
+summary_model = "editor"             # editor (Claude) | bulk (DeepSeek)
+summary_input_tokens = 3000          # article text offered per summary
+
 [publish]
 # Where both EPUB editions land, and what the OPDS feed lists. BookOrbit is
 # optional — it just watches this folder if you run it.