GAM 7.48.26 (automated bump)

[github-actions]

Automated bump of the vendored GAM, 7.48.22 → 7.48.26, via scripts/bump_gam.py.

• Asset build-attestation verified (signed by GAM-team/GAM's release workflow on main) before the pin was written.
• Pin, version strings, test mock, browse catalog and the counts in CLAUDE.md, README and ROADMAP updated mechanically.
• ❌ offline suite RED — needs code changes before merge

Before merge (human): click Approve and run workflows so CI and CodeQL run on this PR
(a PR opened by github.token doesn't start them), and merge only once the required checks are
green. Skim the changelog below, and run scripts/acceptance.py against a real tenant — CI
cannot (it is the only true output-shape check). If the suite is red, the contract test likely
caught a renamed/removed command we use; that needs a code change.

GamUpdate.txt since 7.48.22

7.48.26

Added option `showlabelids` to `gam <UserTypeEntity> print messages|threads ... showlabels countsonly`
that displays label IDs in addition to label names.

7.48.25

Added options `addlabelid <LabelID>` and `removelabelid <LabelID>` to `gam <UserTypeEntity> modify messages`
that avoid the extra API calls required by `addlabel <LabelName>` and `removelabel <LabelName>`.

Added option `oneitemperrow` to `gam <UserTypeEntity> print messages|threads ... showlabels countsonly`
that displays label counts on separate rows rather than in columns on a single row.

7.48.24

Updated `gam <UserTypeEntity> draft|import|insert message` and `gam <UserTypeEntity> sendemail`
with `embedimage <FileName>` to add additional headers to make message compatible with Gmail.

Thanks to @ramonchu

7.48.23

Fixed bug in `gam <UserTypeEntity> draft|import|insert message` and `gam <UserTypeEntity> sendemail`
where `attach <FileName>` and `embedimage <FileName>` were not properly handled.

Thanks to @ramonchu