Fix incorrect javadoc references in ContextStorageProvider and ContextKey

[thswlsqls]

Description

• ContextStorageProvider: the gRPC link text said io.grpc.context.Context, which does not exist — grpc-java declares the class in package io.grpc, and the href on the same line already points at io/grpc/Context.html. (grpc-context is the Maven artifactId, not the package.)
• ContextKey: values of type {@link T} renders as values of type ContextKey, because javadoc resolves the type variable T to the type that declares it, so the sentence says something untrue. No invalid-tag warning is emitted — the reference resolves, just to the wrong thing. {@code T} renders the letter as intended.

Testing done

• Docs-only, test-exempt: no test added; ./gradlew :context:check passed.
• Checked the rendered output with ./gradlew :context:javadoc --rerun-tasks: ContextKey.html now reads values of type <code>T</code>, and ContextStorageProvider.html shows io.grpc.Context.
• No public signature change, so docs/apidiffs/current_vs_latest/ is unchanged.

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Waiting on reviewers · refreshed 2026-08-10 01:36 UTC

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.65%. Comparing base (d948e13) to head (666f49f).

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #8714   +/-   ##
=========================================
  Coverage     91.65%   91.65%           
  Complexity    10352    10352           
=========================================
  Files          1003     1003           
  Lines         27210    27210           
  Branches       3199     3199           
=========================================
  Hits          24939    24939           
  Misses         1566     1566           
  Partials        705      705           

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