Add inner iteration loops to amortize CodSpeed instrumentation overhead

Sub-microsecond benchmarks are dominated by the ~60ns per-iteration
valgrind start/stop cost in CodSpeed simulation mode. Add kInnerIterations
(1000) inner loops to all fast benchmarks so the actual work dominates.
Move DoNotOptimize calls outside inner loops to prevent artificial overhead.

Also address review feedback:
- Use tokenless CodSpeed (public repo, no CODSPEED_TOKEN needed)
- Fix warning message to show component-specific path
- Fix stray ". :" in error message
- Verify pinned SHA on re-runs to prevent stale checkouts

tests/benchmarks/components/api/bench_proto_encode.cpp

@@ -5,6 +5,11 @@
 
 namespace esphome::api::benchmarks {
 
+// Inner iteration count to amortize CodSpeed instrumentation overhead.
+// Without this, the ~60ns per-iteration valgrind start/stop cost dominates
+// sub-microsecond benchmarks.
+static constexpr int kInnerIterations = 1000;
+
 // --- SensorStateResponse (highest frequency message) ---
 
 static void Encode_SensorStateResponse(benchmark::State &state) {
@@ -17,10 +22,13 @@ static void Encode_SensorStateResponse(benchmark::State &state) {
   buffer.resize(size);
 
   for (auto _ : state) {
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
     benchmark::DoNotOptimize(buffer.data());
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(Encode_SensorStateResponse);
 
@@ -31,8 +39,13 @@ static void CalculateSize_SensorStateResponse(benchmark::State &state) {
   msg.missing_state = false;
 
   for (auto _ : state) {
-    benchmark::DoNotOptimize(msg.calculate_size());
+    uint32_t result = 0;
+    for (int i = 0; i < kInnerIterations; i++) {
+      result += msg.calculate_size();
+    }
+    benchmark::DoNotOptimize(result);
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(CalculateSize_SensorStateResponse);
 
@@ -45,12 +58,15 @@ static void CalcAndEncode_SensorStateResponse(benchmark::State &state) {
   msg.missing_state = false;
 
   for (auto _ : state) {
-    uint32_t size = msg.calculate_size();
-    buffer.resize(size);
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
+    for (int i = 0; i < kInnerIterations; i++) {
+      uint32_t size = msg.calculate_size();
+      buffer.resize(size);
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
     benchmark::DoNotOptimize(buffer.data());
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(CalcAndEncode_SensorStateResponse);
 
@@ -84,10 +100,13 @@ static void Encode_BinarySensorStateResponse(benchmark::State &state) {
   buffer.resize(size);
 
   for (auto _ : state) {
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
     benchmark::DoNotOptimize(buffer.data());
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(Encode_BinarySensorStateResponse);
 
@@ -104,10 +123,13 @@ static void Encode_HelloResponse(benchmark::State &state) {
   buffer.resize(size);
 
   for (auto _ : state) {
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
     benchmark::DoNotOptimize(buffer.data());
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(Encode_HelloResponse);
 
@@ -133,10 +155,13 @@ static void Encode_LightStateResponse(benchmark::State &state) {
   buffer.resize(size);
 
   for (auto _ : state) {
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
     benchmark::DoNotOptimize(buffer.data());
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(Encode_LightStateResponse);
 
@@ -157,8 +182,13 @@ static void CalculateSize_LightStateResponse(benchmark::State &state) {
   msg.effect = StringRef::from_lit("rainbow");
 
   for (auto _ : state) {
-    benchmark::DoNotOptimize(msg.calculate_size());
+    uint32_t result = 0;
+    for (int i = 0; i < kInnerIterations; i++) {
+      result += msg.calculate_size();
+    }
+    benchmark::DoNotOptimize(result);
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(CalculateSize_LightStateResponse);
 
@@ -193,8 +223,13 @@ static void CalculateSize_DeviceInfoResponse(benchmark::State &state) {
   auto msg = make_device_info_response();
 
   for (auto _ : state) {
-    benchmark::DoNotOptimize(msg.calculate_size());
+    uint32_t result = 0;
+    for (int i = 0; i < kInnerIterations; i++) {
+      result += msg.calculate_size();
+    }
+    benchmark::DoNotOptimize(result);
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(CalculateSize_DeviceInfoResponse);
 
@@ -205,10 +240,13 @@ static void Encode_DeviceInfoResponse(benchmark::State &state) {
   buffer.resize(total_size);
 
   for (auto _ : state) {
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
+    for (int i = 0; i < kInnerIterations; i++) {
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
     benchmark::DoNotOptimize(buffer.data());
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(Encode_DeviceInfoResponse);
 
@@ -218,12 +256,15 @@ static void CalcAndEncode_DeviceInfoResponse(benchmark::State &state) {
   APIBuffer buffer;
 
   for (auto _ : state) {
-    uint32_t size = msg.calculate_size();
-    buffer.resize(size);
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
+    for (int i = 0; i < kInnerIterations; i++) {
+      uint32_t size = msg.calculate_size();
+      buffer.resize(size);
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+    }
     benchmark::DoNotOptimize(buffer.data());
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(CalcAndEncode_DeviceInfoResponse);
 
@@ -232,13 +273,16 @@ static void CalcAndEncode_DeviceInfoResponse_Fresh(benchmark::State &state) {
   auto msg = make_device_info_response();
 
   for (auto _ : state) {
-    APIBuffer buffer;
-    uint32_t size = msg.calculate_size();
-    buffer.resize(size);
-    ProtoWriteBuffer writer(&buffer, 0);
-    msg.encode(writer);
-    benchmark::DoNotOptimize(buffer.data());
+    for (int i = 0; i < kInnerIterations; i++) {
+      APIBuffer buffer;
+      uint32_t size = msg.calculate_size();
+      buffer.resize(size);
+      ProtoWriteBuffer writer(&buffer, 0);
+      msg.encode(writer);
+      benchmark::DoNotOptimize(buffer.data());
+    }
   }
+  state.SetItemsProcessed(state.iterations() * kInnerIterations);
 }
 BENCHMARK(CalcAndEncode_DeviceInfoResponse_Fresh);