Fixup watcher docs, and watchlist doc examples

[clux]

Lots of missing references in doc builds because we don't have warnings as errors on doc builds. Maybe we should.

Removed the namespace_reflector example because it's a slowly changing thing to watch, and instead added a way to opt-in to WATCHLIST=1 in pod_ and node_ watchers.

Was trying to allow this on event_watcher also but apparently events on k3s do not support sendInitialEvents on 1.27 yet so left it out there. While in the area though, i updated event_watcher to use the new Event type (rather than the legacy core one) to make the example better.

EDIT: follow-up on param serializer might also be needed but doing that separaetly #1281 (comment) - am ultimately not changing the logic anywhere here, just applying clippy suggestions

[codecov]

Codecov Report

Merging #1284 (1e7fd51) into main (f44ce00) will not change coverage.
The diff coverage is n/a.

❗ Current head 1e7fd51 differs from pull request most recent head 5aa37a5. Consider uploading reports for the commit 5aa37a5 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1284   +/-   ##
=======================================
  Coverage   72.27%   72.27%           
=======================================
  Files          75       75           
  Lines        6259     6259           
=======================================
  Hits         4524     4524           
  Misses       1735     1735           

Files Changed	Coverage Δ
kube-core/src/params.rs	84.03% <ø> (ø)
kube-runtime/src/controller/mod.rs	34.21% <ø> (ø)
kube-runtime/src/watcher.rs	38.13% <ø> (ø)

[clux]

Sending this through. It's just docs + examples rest is non-functionally changing clippy stuff.