A need of circuit “philosophy”
The only thing that remains after these good specific circuit solutions is to summarize them by revealing the "philosophy" on which they are built.
The task
For the purposes of these conceptual explanations, I will simplify the OP's task a bit: We need to make an input voltage that varies in the range of -5 V to 5 V…

simulate this circuit – Schematic created using CircuitLab

… vary in the range of 0 V to 10 V.

simulate this circuit

Basic idea
But is not it best to reveal the most general idea first, and then discuss its specific implementations? Because ideas are something eternal that does not depend on specific implementations…
Obviously, the idea here is to add a 5 V offset voltage Voff to the input voltage Vin (Vout = Vin + Voff). Then, when the input voltage varies between -5 V and 5 V, the output voltage will vary between 0 V and 10 V.
Implementation
Simply put, we need a summer to sum the two voltages. What is the simplest way to sum voltages?
Series summer
Apparently, in series according to the KVL is the best way. To do this, we connect the two voltage sources in series, and the whole circuit to the load.

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But what is the summer here? It is what remains after removing the input sources and the load, i.e. a piece of wire ("nothing").

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However, there is a problem - the offset source is floating (ungrounded). If we simply ground it (e.g., through a 1 Ω ammeter SHORT), a short circuit occurs and a high 5 A current flows through Vin.

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The short circuit disappears if we swap the two sources…

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… but the "floating" input source does not suit us either; both sources must be grounded. However, then the load will be "floating"... and we do not want that either.

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How do we solve this last problem? We need a device (an amplifier with a gain of 1) with a “floating” (differential) input and a grounded (single-ended) output.

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This is the solution I proposed to @Tyassin in my comment.
Parallel summer
The solution above needs an op-amp with differential input. But imagine that we have only an amplifier with a single-ended (grounded) input (that was a century ago).
Trying to connect directly Vin and Vref in parallel: Cannot we sum the voltages of the two sources by simply connecting them in parallel? It does not because they come into conflict and a high 5 A current flows.

simulate this circuit
Mitigating the conflict: So, we have to mitigate the conflict by connecting resistors R1 and R2 in series to voltage sources. What is the summer here? It is a little more "complicated" - the two resistors R1 and R2. This humble circuit deserves more attention; so let's examine it manually at three input voltage values:
Vin = -5 V

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Vin = 0 V

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Vin = 5 V

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Finally, let's sweep Vin. What we see is that this circuit both attenuates (two times) and sums the input voltages, i.e. it is a weighted-input summer. As you can see, Vout (in blue) is two times smaller than above (ignore the orange curve; it is only to "cheat" the simulator autoscaling).

Amplified by a non-inverting amplifier: Then let's amplify 2x the output voltage.

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This is the @Tyassin's solution.
Op-amp inverting summer: With the same success we can amplify the output voltage (current) with an inverting (transimpedance) amplifier.

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The only problem is that it is inverted.

This is the left part of the @Math Keeps Me Busy's circuit solution.