fix(agiloft): repoint the block at the alrest surface and fix EWLogin - #6562

…tation

The native Agiloft block could not authenticate against any instance. A
customer reported it; production traces for their workspace confirm every
failure mode verbatim. Fixing that exposed a second, larger problem, and a
per-endpoint audit against the full published documentation found the rest.

Authentication
- EWLogin sent only $KB/$login/$password as query parameters. A live instance
  answers `400 EWWrongDataException ... One has to specify $table, $KB, $lang
  parameters`. $table is required even though only $KB/$login/$password/$lang
  are documented. Parameters now travel in a form-encoded body, which the docs
  permit and which keeps the password out of URLs and access logs.
- The authentication scheme is read from the login response and trimmed;
  Agiloft returns it as "Bearer " with a trailing space.
- EWLogout was missing $lang.

Surfaces
- Record create, read, update, search and saved-search now use the endpoints
  that accept the token EWLogin issues; the legacy operations authenticate from
  inline credentials, which is what that surface expects. Nothing sends both
  forms at once — the documented 400 for doing so is what the original report
  had run into.
- EWSelect passes credentials in a POST body, one of the five operations
  documented to support it.
- Attachment retrieval uses the documented EWRetrieve endpoint, with
  filePosition rather than position, and no longer needs a login/logout pair.

Defects found in the audit
- remove_attachment reported zero on every call: its body is the EWREST
  assignment form but the route ran JSON.parse then Number(), yielding NaN.
- The EWREST parser could not read EWActionButton's documented response, which
  puts both assignments on one line.
- EWLock treated any 200 as success, including the documented
  {error, error_description} envelope, and invented an 'UNKNOWN' status.
- EWTable discarded the linked-field details, required flag and text field type
  it had asked for, making includeLinkedInfo inert.
- select_records had no result ceiling at all; both it and search now cap and
  report a truncated flag rather than reporting a capped length as a total.
- Optional string inputs rejected null, so a blank Page field failed validation
  before any request was made.
- Upsert treated the documented 202 async acknowledgement as a missing-ID
  failure, and returned no callback ID for the caller to poll.
- Every response contract required an output that the 401 and 500 paths never
  return.

Coverage added
- Table and field discovery (EWTable), upsert (EWUpsert), async status
  (EWAsyncStatus), natural language search (EWNLPSearch), action buttons
  (EWActionButton), the REPLACE_WITH_ANOTHER delete rule with its substitute
  records, $async on upsert, and <fieldName>$overwrite on attach.
- Reads with a named field list go through the search projection; an unfiltered
  contract record runs to roughly 184KB and swamps downstream agent context.
- Errors are readable: Agiloft wraps failures in HTML around a typed exception
  and an internal task id, and the JSON endpoints now request real status codes
  rather than a 200 the caller has to interpret.

Not implemented: $searchSQL and $operationHints=NOLOCK are EWRead/EWUpdate
parameters and those operations do not run on that surface here; EWQuestion,
EWHotlinks, EWOData, EWBroadcast and webhook registration have no documentation
beyond their names.

Verified against the published documentation, not against a live instance.

…operations return

Five findings from review that had gone unanswered.

An Agiloft refusal was surfacing as HTTP 500. readAlrestJson throws when the
envelope reports success:false, the route catch mapped that to 500, and the
tool runner retries 500s — so a create the server had already rejected could be
retried and duplicate the record. Refusals now return a settled failure with the
message intact; genuine faults still 500.

list_tables could not run in its primary mode. EWTable is knowledge-base scoped,
but some instances reject EWLogin without a $table, so whole-knowledge-base
discovery failed at login with nothing to fall back to. It now says what the
caller can do about it rather than surfacing the raw login error.

Upsert corrupted structured values. Every field went through String(), so a
multi-value field collapsed into one joined string instead of the documented
repeated key/value pairs, and an object silently wrote "[object Object]" into
the record. Arrays now encode as repeated pairs and objects are refused, since
Agiloft documents no encoding for them.

Two outputs were invisible in the editor. `records` was conditioned on
search_records alone, so natural language search results could not be chained,
and `callbackId` on run_action_button alone, so a queued upsert's callback could
not be wired into Async Status even though both values exist at runtime.