feat: health check method to DaprClient

[matheusandre1]

Description

healthCheck() method to DaprClient that calls the sidecar's /v1.0/healthz endpoint, providing parity with the .NET SDK's CheckHealthAsync.

• waitForSidecar already uses /v1.0/healthz/outbound (done in add health check to wait for sidecar and test it #918), so apps can call Dapr APIs (e.g. read secrets) during startup without waiting for the app channel, which resolves the deadlock described in the issue.
• The remaining ask was a method with the behavior of /v1.0/healthz, which waits for all components, the Dapr HTTP port and the app channel to be ready (Health API docs)

Issue reference

We strive to have all PR being opened based on an issue, where the problem or feature have been discussed prior to implementation.

Closes: #898

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests
• Extended the documentation

[javier-aliaga]

It seems this pr is failing on java 25. @matheusandre1 can you take a look?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.99%. Comparing base (43a5e5d) to head (1831569).

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #1815      +/-   ##
============================================
+ Coverage     78.97%   78.99%   +0.02%     
- Complexity     2586     2591       +5     
============================================
  Files           264      264              
  Lines          7762     7770       +8     
  Branches        815      815              
============================================
+ Hits           6130     6138       +8     
  Misses         1269     1269              
  Partials        363      363              

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