chore(docs): Generate gRPC API documentation

[devsjc]

Fixes a bug whereby adding an initialization timestamp to a
GetForecastAsTimeseries request would then prevent it from returning any
p-values. Also adds documentation.

• Have you followed the Open Climate Fix Contribution Guidelines?
• Have you referenced the Issue this PR addresses, where applicable?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added a summary of the changes?
• Have you written new tests for your changes, where applicable?
• Have you successfully run make lint with your changes locally?
• Have you successfully run make test with your changes locally?

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[github-actions]

Benchmark Results

Benchmark results

Generating Markdown API docs...
?   	github.com/openclimatefix/data-platform/cmd	[no test files]
?   	github.com/openclimatefix/data-platform/internal/gen/ocf/dp	[no test files]
?   	github.com/openclimatefix/data-platform/internal/interceptors	[no test files]
PASS
ok  	github.com/openclimatefix/data-platform/internal/server/dummy	0.005s
{"level":"debug","time":"2026-06-05T14:20:27Z","message":"Completed migrations"}
goos: linux
goarch: amd64
pkg: github.com/openclimatefix/data-platform/internal/server/postgres
cpu: AMD EPYC 9V74 80-Core Processor                
BenchmarkPostgresClient/small/GetForecastAsTimeseries-4         	      67	  17120084 ns/op
BenchmarkPostgresClient/small/GetForecastAtTimestamp-4          	     271	   4196553 ns/op
BenchmarkPostgresClient/small/GetObservationsAsTimeseries-4     	     968	   1181664 ns/op
BenchmarkPostgresClient/small/CreateForecast-4                  	     100	  11475772 ns/op
BenchmarkPostgresClient/small/StreamForecastData-4              	      14	  80068559 ns/op
PASS
ok  	github.com/openclimatefix/data-platform/internal/server/postgres	63.986s
?   	github.com/openclimatefix/data-platform/internal/server/postgres/gen	[no test files]

Benchmark vs base branch

goos: linux
goarch: amd64
pkg: github.com/openclimatefix/data-platform/internal/server/postgres
cpu: AMD EPYC 7763 64-Core Processor                
                                                   │ bench-main.txt │
                                                   │     sec/op     │
PostgresClient/small/GetForecastAsTimeseries-4         17.42m ± ∞ ¹
PostgresClient/small/GetForecastAtTimestamp-4          4.437m ± ∞ ¹
PostgresClient/small/GetObservationsAsTimeseries-4     1.305m ± ∞ ¹
PostgresClient/small/CreateForecast-4                  13.91m ± ∞ ¹
PostgresClient/small/StreamForecastData-4              100.2m ± ∞ ¹
geomean                                                10.71m
¹ need >= 6 samples for confidence interval at level 0.95

cpu: AMD EPYC 9V74 80-Core Processor                
                                                   │ bench-devsjc-docs.txt │
                                                   │        sec/op         │
PostgresClient/small/GetForecastAsTimeseries-4                17.12m ± ∞ ¹
PostgresClient/small/GetForecastAtTimestamp-4                 4.197m ± ∞ ¹
PostgresClient/small/GetObservationsAsTimeseries-4            1.182m ± ∞ ¹
PostgresClient/small/CreateForecast-4                         11.48m ± ∞ ¹
PostgresClient/small/StreamForecastData-4                     80.07m ± ∞ ¹
geomean                                                       9.515m
¹ need >= 6 samples for confidence interval at level 0.95