docs: header sync digram

docs/src/diagrams/header_sync.md

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+## header sync
+```mermaid
+flowchart TD
+    A -..- N1>header_sync.rs line 130]
+    A -..- N2>header_sync/synchronizer.rs line 105]
+    A[synchronize] --> B[1. try sync from all peers]
+    B --> C[2. connect and attempt sync]
+    C --> D[3. attemp sync]
+    D -..- N3>header_sync/synchronizer.rs line 284]
+    D --> E[(get local tip header)]
+    E --> F[["Determine sync status"]]
+    F--> G{SyncStatus?}    
+    G --> |Lagging|M[["synchronize_headers (see synchronize_headers.md)"]]
+    G --> |InSync|H[(Get local chain metadata height)]
+    G --> |WereAhead|H[(Get local chain metadata height)]
+    H --> I{metadata < local_chain_header}
+    I --> |true|J[return event:HeadersSynchronized]
+    I --> |false|K{starting local metdata < remote peer metadata}
+    K --> |true|J
+    K --> |False| L[ban remote peer]
+    L --> N[return event::Continue]
+    M --> J
+
+
+    N1:::note
+    N2:::note
+    N3:::note
+   classDef note fill:#eee,stroke:#ccc
+```
+## determine sync status
+```mermaid
+flowchart TD
+    A -..- N1>header_sync/synchronizer.rs line 434]
+    A[determine sync status] --> B[1. find chain split]
+    B -..- N2>header_sync/synchronizer.rs line 364]
+    B --> C[(fetch 500 headers back)]
+    C --> D[2.Send headers to remote peer for matching]
+    D --> E{Result back}
+    E -->|RPC::RequestFailed|C  
+    E -->|Some headers returned|F{3.Too much headers returned}
+    F --> |Yes| G[ban peer]
+    F --> |No|I{4.bad data returned}
+    I --> |Yes| G
+    I --> |No|J{5.No headers returned}
+    J --> |Yes|K{6.returned forked inde > 0}
+    K --> |Yes|L[return WereAhead]
+    K --> |No|M[return Insync]
+    J --> |No|N[7.validater returned headers]
+    N --> O{8. remote peer tip height < split height}
+    O --> |Yes| G
+    O --> |No|P[return Lagging]
+
+
+    N1:::note
+    N2:::note
+   classDef note fill:#eee,stroke:#ccc
+```
+
+## synchronise headers
+```mermaid
+flowchart TD
+    A -..- N1>header_sync/synchronizer.rs line 566]
+    A[synchronie_headers] --> B{1. Compare PoW}
+    B --> |Yes| C[2.Switch chain to pending chain]
+    C --> D[Rewind chain if desired]
+    D --> E[Commit headers to database and main chain]
+    B --> |No|F{3. pending header len < max request num}
+    E --> |No|F
+    F --> |Yes|G{4. Compare PoW}
+    G --> |No|H[ban peer]
+    F --> |No| I[5. Sync headers stream]
+    G --> |Yes| I
+    I --> J[6. Stream get next header]
+    J -->|some header| K[(Get local chain metadata height)]
+    K --> L{7.existing header?}
+    L --> |Yes|J
+    L --> |No|M[8. validate header]
+    M --> N{has switched to new chain}
+    N --> |Yes|O[commit new header]
+    N --> |No| P{9.compare chains}
+    P --> |Yes| Q[swap chains -> C]
+    P --> |No| J
+    J --> |None| R{has switched to new chain}
+    R --> |No|S{Remote peer metadata < current temp metdata}
+    R --> |Yes|V[commit last headers, return ok]
+    S --> |Yes|T[ban peer]
+    S --> |No| U[Return Ok]
+
+    N1:::note
+   classDef note fill:#eee,stroke:#ccc
+```
+
+```mermaid
+flowchart TD
+    A[attempt_sync] -->B[determine_sync_status]
+    A -..- DB>DB access featch last header]
+    B -..- N1>synchronizer.rs line 434]
+
+    B --> C[fn find_chain_split]
+    C -..- N2>synchronizer.rs line 364]
+
+    C -->|remote peer| D[fn find_chain_split]
+    D -..- N3>sync/rpc/service.rs line 364]
+
+    D -->|GRAPH REMOTE|E[[fn determine_sync_status]]    
+    E -..- N1>synchronizer.rs line 434]
+
+    E -->|empty_headers|K[Is fork hash > 0]
+    K --> |true| L[Return we are ahread]
+    K --> |false|G[Return insync]
+    E -->|too many returned|F[ban peer]
+    E -->|index >= hashes returned|F[Return ban peer]
+    L --> |Check if our meta data has changed|M[ban peer on true]
+    G --> |Check if our meta data has changed|M[ban peer on true]
+    E -->|iterate over returned headers| H[Validate initial headers]
+    H --> I[is split height greater than claimed height]
+    I -->|No|F[Return ban peer]
+    I --> J[Lagging state]
+    J --> N[fn Synchroize_headers]
+    N -..- N4>synchronizer.rs line 566]
+
+    N --> O[is intial headers pow's higher than current chain]
+    O --> |Yes|P[swap to chain to intial headers]    
+    O --> |No|Q[Has peer sent max headers]
+    P --> Q[Has peer sent max headers]
+    Q --> |No|R[is intial headers pow's higher than current chain]
+    R --> |No|S[ban peer]
+    R --> |Yes|T[Exit header sync, go to block sync]
+    Q --> |Yes|U[iterate over header stream]
+    U --> V[Does it follow prev header]
+    V --> |No|W[ban peer]
+    V --> |Yes|X[Does it already exist in chain] 
+    X --> |Yes|W[ban peer]
+    X --> |No|Y[validate] 
+    Y --> |No|W[ban peer]
+    Y --> |Yes|Z[Have we swapped to new chain]
+    Z --> |Yes|AA[Add to main chain]
+    Z --> |No|AB[is the new temp chain's pow higher than the local chain]
+    AB --> |Yes|AC[Swap to new chain]
+    AC --> AD[End of header stream]
+    Z --> AD[End of header stream]
+    AD --> |No|U
+    AD --> |Yes|AE[Have we swapped chains]
+    AE --> |No|AF[is the temp chains'pow less than originally claimed by the peer]
+    AF --> |Yes|W
+    AF --> |No|AG[local chain is higher, exit sync]
+    AE --> AH[is new chains'pow less than originally claimed by the peer]
+    AH --> |Yes|W
+    AH --> |No|AI[Go on to block sync]
+
+    N1:::note
+    N2:::note
+    N3:::note
+    N4:::note
+    DB:::note
+    classDef note fill:#eee,stroke:#ccc
+    ```

docs/src/diagrams/listing_state.rs

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+```mermaid
+flowchart TD
+    A -..- N1>listening.rs line 128]
+    A --> |Network Silence| A
+    A --> |PeerChainMetadataReceived| B{1. Is peer banned}
+    B --> |True|A
+    B --> |False| C[(2. save peer info)]
+    C --> D{3. Is forced synced peers on}
+    D --> |Yes|E{4. Is this a forced sync peer}
+    E --> |No| A
+    D --> |No| F[(get local chain metadata)]
+    E --> |Yes| F
+    F --> G{5.Is synced & 1 block behind remote peer & wait less 20s since received}
+    G --> |Yes| A
+    G --> |No| H[(get local chain metadata)]
+    H --> I[7.determine_sync_mode]
+    I -..- N2>listening.rs line 273]
+    I --> J{8. Local metadat < Remote metadata}
+    J --> |Yes| K[9. Local height + lagging blocks > network height]
+    K --> |Yes| A 
+    K --> |No| L[return FallenBehind]
+    J --> |No| A
+
+
+
+    N1:::note
+    N2:::note
+   classDef note fill:#eee,stroke:#ccc
+   ```

docs/src/diagrams/state_machine.rs

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+```mermaid
+flowchart TD
+    A -..- N1>state_machine.rs line 231]
+    A[starting_state] --> |Initialized|B[["Listen_state (see listen_state.md)"]]
+    B --> |FallenBehind| C[HeaderSync]
+
+
+
+
+    N1:::note
+    N2:::note
+    N3:::note
+    N4:::note
+    classDef note fill:#eee,stroke:#ccc
+    ```