fix(projekt-matching): break infinite alert loop (issue 2)

Root cause chain (evidence: 25+ failed traces on nproj/3022414):
straight quote in page text ends the guided-decoding JSON string
early -> grammar deadlock -> whitespace loop until context/token
limit -> chat_json fails 3x (~35 min) -> IMAP conn idles out ->
move_to_trash raises -> mail never trashed -> reprocessed forever.

- ingest/mailer: MailBox.ensure_alive() reconnect before finalize;
  move_to_trash failure falls back to flag_checked, run continues
- stages: page_text() feeds only div.content minus skill-tag cloud
  to the LLM and maps quote chars to apostrophes (the actual
  degeneration trigger, live-verified: extract now OK in 21 s)
- llm: requirements maxItems 40; max_tokens 8192 caps degenerate
  runs at ~100 s instead of ~10 min

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

projekt-matching/projektmatch/stages.py

@@ -20,6 +20,7 @@ TEAM_BY_OFFER = {"Projekt": "DesTEngS",
                  "Arbeitnehmer-Angebot": "Arbeitnehmer",
                  "ANÜ": "ANÜ"}
 MIN_PAGE_CHARS = 200
+QUOTES = str.maketrans({c: "'" for c in "„“”\"«»‹›"})
 
 
 def run_stage(name, fn, ctx, cfg, **kw):
@@ -32,6 +33,25 @@ def run_stage(name, fn, ctx, cfg, **kw):
         return ctx
 
 
+def page_text(html):
+    """Project text for the LLM: header + description, WITHOUT the skill-tag
+    cloud (div.project-body-badges, ~100 entries on some pages — blows the
+    requirements list up until the model emits broken JSON) and without
+    site chrome. Falls back to whole-page text if div.content is missing."""
+    soup = BeautifulSoup(html, "html.parser")
+    for tag in soup(["script", "style", "noscript"]):
+        tag.decompose()
+    root = soup.find("div", class_="content") or soup
+    for tag in root.find_all(class_="project-body-badges"):
+        tag.decompose()
+    # Anführungszeichen -> Apostroph: ein wörtlich übernommenes " beendet den
+    # JSON-String vorzeitig und treibt guided decoding in eine Whitespace-
+    # Endlosschleife (finish_reason "length", live verifiziert an nproj/3022414)
+    return "\n".join(line for line in
+                     root.get_text("\n", strip=True).splitlines()
+                     if line.strip()).translate(QUOTES)
+
+
 def stage_fetch(ctx, cfg):
     last = None
     for attempt in range(3):
@@ -39,12 +59,7 @@ def stage_fetch(ctx, cfg):
             resp = requests.get(ctx["canonical"], timeout=30,
                                 headers={"User-Agent": BROWSER_UA})
             resp.raise_for_status()
-            soup = BeautifulSoup(resp.text, "html.parser")
-            for tag in soup(["script", "style", "noscript"]):
-                tag.decompose()
-            text = "\n".join(line for line in
-                             soup.get_text("\n", strip=True).splitlines()
-                             if line.strip())
+            text = page_text(resp.text)
             if len(text) < MIN_PAGE_CHARS:
                 raise ValueError(
                     f"Seitentext zu kurz ({len(text)} Zeichen) — "