fix(scripts): fall through on spent lookups, send the key in both places

A 429 on the lookup no longer waits for the Retry-After; the keyed upload
answers the same question. The source key goes in the query string and the
form. The closing summary and the guide point to Read with AI for deferred
documents instead of Index all.

Refs #1038

docs/integrations/document-import.md

@@ -60,7 +60,8 @@ change the type in HealthLog.
 
 Tagging a document again, or editing it in Paperless, fires the workflow
 again. That is harmless: HealthLog recognises the Paperless document id and
-answers "already stored". If you delete the document in HealthLog, a later
+answers "already stored", though each re-send still counts towards the
+token's hourly limit. If you delete the document in HealthLog, a later
 re-send does not bring it back.
 
 **What the workflow is not for.** Paperless gives up on a webhook after
@@ -150,7 +151,8 @@ What it does:
 - When HealthLog asks it to slow down, it waits as long as HealthLog says
   and carries on. By default a document token may upload 120 documents an
   hour, so an archive of a thousand documents takes an evening. Documents
-  HealthLog already has do not count towards that. Uploads you make yourself
+  HealthLog already has do not count towards that, because the script asks
+  before sending them. Uploads you make yourself
   in the web app or on your phone are counted separately and are not held
   up.
 - At the end it prints how many documents were imported, how many were
@@ -169,11 +171,11 @@ thousand AI requests at once. Imported documents still get a preview and
 are searchable by their text where the file has a text layer.
 
 HealthLog remembers that these documents were held back: turning on
-automatic AI reading later does not send them to your AI provider either.
-To have documents read, open one and choose **Read with AI** or
-**Generate summary**, or use **Index all for search** in Documents for the
-ones that had no text to search. Pass `--ai-read` if you do want every
-imported document read as it arrives.
+automatic AI reading later does not send them to your AI provider, and
+**Index all for search** in Documents leaves them out too. To have a
+document read, open it and choose **Read with AI** or **Generate summary**.
+Pass `--ai-read` if you do want every imported document read as it
+arrives.
 
 The Paperless workflow does not hold AI reading back: new documents are
 treated like any other upload.
@@ -213,6 +215,11 @@ per account: if you push documents from two other systems, make sure their
 ids cannot collide, for example by prefixing them (`nextcloud-123`,
 `scanner-123`).
 
+When the same file arrives under a second id (the same scan in the source
+twice, or a file you had uploaded by hand), HealthLog keeps one copy and
+remembers the extra id for it. One document takes up to 20 such ids; a
+21st is refused with a message, and nothing is stored.
+
 ## For operators
 
 `DOCUMENT_UPLOAD_LIMIT_PER_HOUR` sets how many documents one document token