[ Reason ]
Four Changes. 3 CVE patch backports, and a fix for our CI.

1. Backport of upstream patch for CVE-2026-8286.
   In backporting, the changes were mostly context refreshes.
   A few variables changed names, and a struct member had been
   moved in upstream, and I moved it back.

2. Backport of upstream patch for CVE-2026-8924.
   In backporting, I had to cleanup the Makefile, and change
   how the test declared usage of crlf line endings.

3. Backport of upstream patch for CVE-2026-8927.
   In backporting, the changes were of context refresh,
   variable name changes (used in macros),
   changes to error codes expected in tests (changed upstream),
   changes to crlf line endings in the test,
   replace internal libs imports,
   removal of a feature gate that does not exists in our version,
   and changed where a ifndef block is applied.

4. Additionally, I updated the debian/watch file by cherry-picking
   the same file from the debian/sid branch. This does not affect the
   package in stable, but fixes our CI pipelines that would otherwise
   always fail the "test-uscan" step.

[ Impact ]
The 3 CVEs could affect the user security if exploited by bad actors.

[ Tests ]
The autopkgtests (which run upstreams test suite, including "make
checksrc") pass again with this upload.

All 3 CVEs come with new regression tests added by upstream,
and the tests were backported to work correctly in our version.

[ Risks ]
Low. The 3 patches exists in upstream (and Debian Unstable),
and there is no known regressions involved.
The debian/watch change has no impact at all on the package.
The first two CVEs were almost trivial to backport.
The third (CVE-2026-8927) was a bit more complex, as upstream
changed the orther of some operations. But it is a simple patch.

[ Checklist ]
  [x] *all* changes are documented in the d/changelog
  [x] I reviewed all changes and I approve them
  [x] attach debdiff against the package in stable
  [x] the issue is verified as fixed in unstable

[ Changes ]

* Import upstream patches for 3 CVE fixes:
    - CVE-2026-8286
    - CVE-2026-8924
    - CVE-2026-8927
https://salsa.debian.org/rcpassos/curl/-/commit/c56a3f9967fd1b1638f3592c082f71d3f605916f
* Backport patch CVE-2026-8286
https://salsa.debian.org/rcpassos/curl/-/commit/e6831b59e027e5898f346fe4d0e9ec392001a32a
* Backport patch CVE-2026-8924
https://salsa.debian.org/rcpassos/curl/-/commit/d161f81735b759243747432af4b3e2692d206b19
* Backport patch CVE-2026-8286
https://salsa.debian.org/rcpassos/curl/-/commit/c10983925ac24c2d83afed3931ac36b216689bd9
* Cherry-pick change to debian/watch from debian unstable
https://salsa.debian.org/rcpassos/curl/-/commit/60d871f7d60c0cbca423fe5dab21ff6e33224f0c

[ Other info ]
This is my first backport, but I had the guidance and patience
of Samuel Henrique, who helped me accomplish this PU.