Document typical flow

docs/internals/typical_query.md

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+The following sequence diagram shows the typical flow of a query from the CLI to the VDBE.
+
+```mermaid
+sequenceDiagram
+
+participant main as cli/main
+participant Database as core/lib/Database
+participant Connection as core/lib/Connection
+participant Statement as core/lib/Statement
+participant Parser as sql/mod/Parser
+participant Scanner as sql/mod/Scanner
+participant translate as translate/mod
+participant Program as vdbe/mod/Program
+
+main->>Database: open_file
+Database->>main: Connection
+main->>Connection: query(sql)
+Note right of Parser: Uses vendored sqlite3-parser
+Connection->>Parser: next()
+Note left of Parser: Passes the SQL query to Parser
+
+Parser->>Scanner: scan()
+Scanner->>Parser: returns tokens
+
+
+Parser->>Connection: Cmd::Stmt
+Connection->>translate:translate() 
+
+Note left of translate: Translates SQL statement into bytecode
+
+Connection->>main: Ok(Some(Rows { Statement }))
+main->>Statement: step()
+Statement->>Program: step()
+Note left of Program: Executes bytecode instructions<br />See https://www.sqlite.org/opcode.html
+Program->>Statement: StepResult
+Statement->>main: StepResult
+```