Fix sample code in SQL querying page

[roji]

Our conceptual docs generally show SQL Server code, but the samples are designed to work against Sqlite (so they can run out of the box). Inlined sample code into the SQL querying page, which seems to be our general direction anyway.

Fixes #4919

[Copilot]

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (8)

samples/core/Querying/SqlQueries/Program.cs:53

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"SELECT * FROM dbo.Blogs")

samples/core/Querying/SqlQueries/Program.cs:60

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"EXECUTE dbo.GetMostPopularBlogs")

samples/core/Querying/SqlQueries/Program.cs:69

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"EXECUTE dbo.GetMostPopularBlogsForUser {user}")

samples/core/Querying/SqlQueries/Program.cs:78

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"EXECUTE dbo.GetMostPopularBlogsForUser @filterByUser={user}")

samples/core/Querying/SqlQueries/Program.cs:87

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"EXECUTE dbo.GetMostPopularBlogsForUser {user}")

samples/core/Querying/SqlQueries/Program.cs:106

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"SELECT * FROM dbo.SearchBlogs({searchTerm})")

samples/core/Querying/SqlQueries/Program.cs:117

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"SELECT * FROM dbo.SearchBlogs({searchTerm})")

samples/core/Querying/SqlQueries/Program.cs:127

• The 'dbo.' prefix is specific to SQL Server and should be removed or replaced with the appropriate SQLite syntax.

.FromSql($"SELECT * FROM dbo.SearchBlogs({searchTerm})")

[AndriySvyryd]

Inlined sample code into the SQL querying page, which seems to be our general direction anyway.

The general direction is to keep them in projects, so that they can be run to ensure that they are still working.

[AndriySvyryd]

Remove this file if it's no longer being referenced.

[roji]

#4931