feat: add company showcase and update to v1.0.0-alpha3

- Add "Trusted by" section showcasing PlanFact as production user
- Update version to 1.0.0-alpha3 in project file and README
- Add call-to-action for other companies to share their usage

This release includes the configuration validation and performance
improvements from the previous commit.

Author: akrisanov

README.md

@@ -249,7 +249,7 @@ builder.Services.AddOpenTelemetry()
 
 ## Roadmap / Status
 
-- Current version: pre-release (1.0.0-alpha1)
+- Current version: pre-release (1.0.0-alpha3)
 
 ### Planned features
 
@@ -268,6 +268,14 @@ builder.Services.AddOpenTelemetry()
 
 Contributions and feedback are welcome to help shape the API and features.
 
+## Trusted by
+
+Companies using HttpClient.Resilience in production:
+
+[![planfact.io](https://planfact.io/build/images/icons/72.png)](https://planfact.io)
+
+_Using HttpClient.Resilience in production? [Let us know](https://github.com/akrisanov/HttpClient.Resilience/issues) and we'll add your company here!_
+
 ## Contributing
 
 Contributions are encouraged! Please open issues or pull requests on the GitHub repository.

src/HttpClient.Resilience/HttpClient.Resilience.csproj

@@ -3,9 +3,10 @@
     <TargetFrameworks>net6.0;net8.0;net9.0</TargetFrameworks>
     <AssemblyName>HttpClient.Resilience</AssemblyName>
     <PackageId>HttpClient.Resilience</PackageId>
-    <Version>1.0.0-alpha1</Version>
-    <PackageReleaseNotes>Initial alpha release with retry policies, circuit breaker,
-      HttpClientOptions, and base response handler.</PackageReleaseNotes>
+    <Version>1.0.0-alpha3</Version>
+    <PackageReleaseNotes>Added configuration validation, performance improvements with specific
+      return types,
+      and suppressed .NET 6.0 compatibility warnings.</PackageReleaseNotes>
     <Authors>Andrey Krisanov</Authors>
     <Company></Company>
     <Description>Lightweight resilience helpers (retry with jitter, circuit breaker) and response
@@ -22,6 +23,9 @@
     <EmbedUntrackedSources>true</EmbedUntrackedSources>
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
     <DebugType>portable</DebugType>
+    <!-- Suppress warnings about Microsoft.Extensions.* 9.x not officially supporting .NET 6.0 -->
+    <!-- These packages work fine with .NET 6.0 in practice -->
+    <SuppressTfmSupportBuildWarnings>true</SuppressTfmSupportBuildWarnings>
   </PropertyGroup>
 
   <ItemGroup>