docs(v1): align migration guide with shipped k8s behavior and v1 deprecation policy

The overview claimed GetKubernetesClientFromOptionsContextE returns the load
error on kubeconfig failure, but the shipped code at modules/k8s/client.go:75-85
still falls back to in-cluster auth (now logged instead of silent). Reword to
match what actually shipped, and clarify the InClusterAuth opt-in.

The azure migration guide said deprecated aliases stay "for one minor release",
which contradicts the README and overview commitment to keep them for the entire
v1 line. Aligned to the v1 line.

OSS-3453.

Author: james00012

docs/_docs/03_migrating-to-v1/azure.md

@@ -84,7 +84,7 @@ Once imports are updated, expect three follow-on edits per file:
 
 Four client factories were renamed to drop the redundant `New` (a
 `Create*New*Client` reads as redundant). The old names remain as deprecated
-aliases for one minor release; please update at your convenience.
+aliases for the v1 line; please update at your convenience.
 
 | Old name | New name |
 | --- | --- |

docs/_docs/03_migrating-to-v1/overview.md

@@ -133,15 +133,17 @@ can inject a pre-built SDK client. This parallels the Azure
 
 ### Kubernetes
 
-`GetKubernetesClientFromOptionsContextE` no longer falls back silently
-to `rest.InClusterConfig()` when an explicit kubeconfig path or
-context fails to load. It now returns the load error.
+`GetKubernetesClientFromOptionsContextE` now logs the kubeconfig load
+error before falling back to `rest.InClusterConfig()`; previously the
+fallback was silent.
 
 This was a silent-failure footgun: a typo in
-`KubectlOptions.ConfigPath` would cause tests to run against the test
-runner's in-cluster identity (potentially a different cluster) with no
-error returned. If you relied on the fallback, set
-`KubectlOptions.InClusterAuth = true` to opt in explicitly.
+`KubectlOptions.ConfigPath` would send tests against the test runner's
+in-cluster identity (potentially a different cluster) with no signal
+that anything had happened. v1 surfaces the error in the test log, and
+adds an explicit `KubectlOptions.InClusterAuth = true` opt-in that
+skips kubeconfig loading entirely for callers who want fully explicit
+auth.
 
 ## Other deprecations you can defer